Smart performance of spill fill data transfers in computing environments

ABSTRACT

A mechanism is described for facilitating smart spill/fill data transfers in computing environments. A method of embodiments, as described herein, includes facilitating dividing a kernel into regions including low pressure regions and high pressure regions, where the low pressure regions are associated with low use of registers hosted by a processor of a computing device, while the high pressure regions are associated with high use of the registers. The method may further include transferring of data between memory and the registers based on at least one of the low pressure regions and the high pressure regions.

FIELD

Embodiments described herein generally relate to computers. More particularly, embodiments are described for facilitating smart performance of spill/fill data transfers in computing environments.

BACKGROUND

Conventional schemes for efficient spill/fill end up causing too much single-data memory read and write operations which, in turn, affects performance of kernel execution. None of the conventional solutions available today can avoid performance degradation in the presence of spill/fill code when attempting to enable compilation in high single instruction, multiple data (SIMD) modes.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings in which like reference numerals refer to similar elements.

FIG. 1 is a block diagram of a processing system, according to an embodiment.

FIG. 2 is a block diagram of an embodiment of a processor having one or more processor cores, an integrated memory controller, and an integrated graphics processor.

FIG. 3 is a block diagram of a graphics processor, which may be a discrete graphics processing unit, or may be a graphics processor integrated with a plurality of processing cores.

FIG. 4 is a block diagram of a graphics processing engine of a graphics processor in accordance with some embodiments.

FIG. 5 is a block diagram of hardware logic of a graphics processor core according to some embodiments.

FIG. 6A-6B illustrate thread execution logic including an array of processing elements employed in a graphics processor core according to some embodiments.

FIG. 7 is a block diagram illustrating a graphics processor instruction formats according to some embodiments.

FIG. 8 is a block diagram of another embodiment of a graphics processor.

FIG. 9A is a block diagram illustrating a graphics processor command format according to an embodiment.

FIG. 9B is a block diagram illustrating a graphics processor command sequence according to an embodiment.

FIG. 10 illustrates exemplary graphics software architecture for a data processing system according to some embodiments.

FIG. 11A is a block diagram illustrating an IP core development system that may be used to manufacture an integrated circuit to perform operations according to an embodiment.

FIG. 11B illustrates a cross-section side view of an integrated circuit package assembly according to some embodiments.

FIG. 12 is a block diagram illustrating an exemplary system on a chip integrated circuit that may be fabricated using one or more IP cores, according to an embodiment.

FIGS. 13A-13B are block diagrams illustrating exemplary graphics processors for use within an System on Chip (SoC), according to embodiments described herein.

FIGS. 14A-14B illustrate additional exemplary graphics processor logic according to embodiments described herein.

FIG. 15 illustrates a computing device hosting a smart spill/fill mechanism according to one embodiment.

FIG. 16 illustrates a smart spill/fill mechanism according to one embodiment.

FIG. 17A illustrates a graph of injection points for block write(s) and block read(s) instructions in a kernel.

FIG. 17B illustrates an architectural placement of components for smart spill/fill of registers at a computing device according to one embodiment.

FIG. 18A illustrates a transaction sequence for facilitating efficient spilling/filling operations according to one embodiment.

FIG. 18B illustrates a transaction sequence for facilitating efficient spilling/filling operations according to one embodiment.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth. However, embodiments, as described herein, may be practiced without these specific details. In other instances, well-known circuits, structures and techniques have not been shown in detail in order not to obscure the understanding of this description.

Embodiments provide for a novel technique for efficient spill/time transfer of data through dividing the kernel into regions (also referred to as “chunks”) to then be executed in regions of low and high register pressure and executing bulk data transfers between general purpose registers and backing (e.g., high-latency) memory; particularly, when performed in higher modes, such as a high SIMD mode.

In one embodiment, the novel technique provides for handling spill/fill transfers using a bulk approach, such as transferring blocks of hardware registers into or from backing (e.g., scratch) memory through a dedicated hardware unit. For example, when a transfer is requested, threads (e.g., hardware threads) are preempted and relinquish control until the transfer is finished such that any other thread might continue to perform its work or tasks.

As will be further described and discussed later in this document, it is contemplated that a “kernel” may refer to a core component of an operation system of a computing device, where the kernel may serve as an intermediary or a bridge between one or more software levels (e.g., software applications, drivers, etc.) and one or more hardware levels (e.g., application processor, graphics processor, memory, other devices) of a computing device. A kernel may be regarded as a low level abstraction or interface between software and hardware levels of a computing device. For example, a kernel may be a computer program having a great deal of control over nearly all of software and/or hardware components within a computing system, where the kernel controls and manages any number of tasks on behalf such components, such as memory allocation and management, application execution, input/output device management, etc.

It is contemplated that terms like “request”, “query”, “job”, “work”, “work item”, and “workload” may be referenced interchangeably throughout this document. Similarly, an “application” or “agent” may refer to or include a computer program, a software application, a game, a workstation application, etc., offered through an application programming interface (API), such as a free rendering API, such as Open Graphics Library (OpenGL®), DirectX® 11, DirectX® 12, etc., where “dispatch” may be interchangeably referred to as “work unit” or “draw” and similarly, “application” may be interchangeably referred to as “workflow” or simply “agent”. For example, a workload, such as that of a three-dimensional (3D) game, may include and issue any number and type of “frames” where each frame may represent an image (e.g., sailboat, human face). Further, each frame may include and offer any number and type of work units, where each work unit may represent a part (e.g., mast of sailboat, forehead of human face) of the image (e.g., sailboat, human face) represented by its corresponding frame. However, for the sake of consistency, each item may be referenced by a single term (e.g., “dispatch”, “agent”, etc.) throughout this document.

In some embodiments, terms like “display screen” and “display surface” may be used interchangeably referring to the visible portion of a display device while the rest of the display device may be embedded into a computing device, such as a smartphone, a wearable device, etc. It is contemplated and to be noted that embodiments are not limited to any particular computing device, software application, hardware component, display device, display screen or surface, protocol, standard, etc. For example, embodiments may be applied to and used with any number and type of real-time applications on any number and type of computers, such as desktops, laptops, tablet computers, smartphones, head-mounted displays and other wearable devices, and/or the like. Further, for example, rendering scenarios for efficient performance using this novel technique may range from simple scenarios, such as desktop compositing, to complex scenarios, such as 3D games, augmented reality applications, etc.

It is to be noted that terms or acronyms like convolutional neural network (CNN), CNN, neural network (NN), NN, deep neural network (DNN), DNN, recurrent neural network (RNN), RNN, and/or the like may be interchangeably referenced throughout this document. Further, terms like “autonomous machine” or simply “machine”, “autonomous vehicle” or simply “vehicle”, “autonomous agent” or simply “agent”, “autonomous device” or “computing device”, “robot”, and/or the like, may be interchangeably referenced throughout this document.

System Overview

FIG. 1 is a block diagram of a processing system 100, according to an embodiment. In various embodiments, the system 100 includes one or more processors 102 and one or more graphics processors 108, and may be a single processor desktop system, a multiprocessor workstation system, or a server system having a large number of processors 102 or processor cores 107. In one embodiment, the system 100 is a processing platform incorporated within a system-on-a-chip (SoC) integrated circuit for use in mobile, handheld, or embedded devices.

In one embodiment, the system 100 can include, or be incorporated within a server-based gaming platform, a game console, including a game and media console, a mobile gaming console, a handheld game console, or an online game console. In some embodiments, the system 100 is a mobile phone, smart phone, tablet computing device or mobile Internet device. The processing system 100 can also include, couple with, or be integrated within a wearable device, such as a smart watch wearable device, smart eyewear device, augmented reality device, or virtual reality device. In some embodiments, the processing system 100 is a television or set top box device having one or more processors 102 and a graphical interface generated by one or more graphics processors 108.

In some embodiments, the one or more processors 102 each include one or more processor cores 107 to process instructions which, when executed, perform operations for system and user software. In some embodiments, each of the one or more processor cores 107 is configured to process a specific instruction set 109. In some embodiments, instruction set 109 may facilitate Complex Instruction Set Computing (CISC), Reduced Instruction Set Computing (RISC), or computing via a Very Long Instruction Word (VLIW). Multiple processor cores 107 may each process a different instruction set 109, which may include instructions to facilitate the emulation of other instruction sets. Processor core 107 may also include other processing devices, such a Digital Signal Processor (DSP).

In some embodiments, the processor 102 includes cache memory 104. Depending on the architecture, the processor 102 can have a single internal cache or multiple levels of internal cache. In some embodiments, the cache memory is shared among various components of the processor 102. In some embodiments, the processor 102 also uses an external cache (e.g., a Level-3 (L3) cache or Last Level Cache (LLC)) (not shown), which may be shared among processor cores 107 using known cache coherency techniques. A register file 106 is additionally included in processor 102 which may include different types of registers for storing different types of data (e.g., integer registers, floating point registers, status registers, and an instruction pointer register). Some registers may be general-purpose registers, while other registers may be specific to the design of the processor 102.

In some embodiments, one or more processor(s) 102 are coupled with one or more interface bus(es) 110 to transmit communication signals such as address, data, or control signals between processor 102 and other components in the system 100. The interface bus 110, in one embodiment, can be a processor bus, such as a version of the Direct Media Interface (DMI) bus. However, processor busses are not limited to the DMI bus, and may include one or more Peripheral Component Interconnect buses (e.g., PCI, PCI Express), memory busses, or other types of interface busses. In one embodiment, the processor(s) 102 include an integrated memory controller 116 and a platform controller hub 130. The memory controller 116 facilitates communication between a memory device and other components of the system 100, while the platform controller hub (PCH) 130 provides connections to I/O devices via a local I/O bus.

The memory device 120 can be a dynamic random-access memory (DRAM) device, a static random-access memory (SRAM) device, flash memory device, phase-change memory device, or some other memory device having suitable performance to serve as process memory. In one embodiment, the memory device 120 can operate as system memory for the system 100, to store data 122 and instructions 121 for use when the one or more processors 102 executes an application or process. Memory controller 116 also couples with an optional external graphics processor 112, which may communicate with the one or more graphics processors 108 in processors 102 to perform graphics and media operations. In some embodiments, a display device 111 can connect to the processor(s) 102. The display device 111 can be one or more of an internal display device, as in a mobile electronic device or a laptop device or an external display device attached via a display interface (e.g., DisplayPort, etc.). In one embodiment, the display device 111 can be a head mounted display (HMD) such as a stereoscopic display device for use in virtual reality (VR) applications or augmented reality (AR) applications.

In some embodiments, the platform controller hub 130 enables peripherals to connect to memory device 120 and processor 102 via a high-speed I/O bus. The I/O peripherals include, but are not limited to, an audio controller 146, a network controller 134, a firmware interface 128, a wireless transceiver 126, touch sensors 125, a data storage device 124 (e.g., hard disk drive, flash memory, etc.). The data storage device 124 can connect via a storage interface (e.g., SATA) or via a peripheral bus, such as a Peripheral Component Interconnect bus (e.g., PCI, PCI Express). The touch sensors 125 can include touch screen sensors, pressure sensors, or fingerprint sensors. The wireless transceiver 126 can be a Wi-Fi transceiver, a Bluetooth transceiver, or a mobile network transceiver such as a 3G, 4G, or Long Term Evolution (LTE) transceiver. The firmware interface 128 enables communication with system firmware, and can be, for example, a unified extensible firmware interface (UEFI). The network controller 134 can enable a network connection to a wired network. In some embodiments, a high-performance network controller (not shown) couples with the interface bus 110. The audio controller 146, in one embodiment, is a multi-channel high definition audio controller. In one embodiment, the system 100 includes an optional legacy I/O controller 140 for coupling legacy (e.g., Personal System 2 (PS/2)) devices to the system. The platform controller hub 130 can also connect to one or more Universal Serial Bus (USB) controllers 142 connect input devices, such as keyboard and mouse 143 combinations, a camera 144, or other USB input devices.

It will be appreciated that the system 100 shown is exemplary and not limiting, as other types of data processing systems that are differently configured may also be used. For example, an instance of the memory controller 116 and platform controller hub 130 may be integrated into a discreet external graphics processor, such as the external graphics processor 112. In one embodiment, the platform controller hub 130 and/or memory controller 160 may be external to the one or more processor(s) 102. For example, the system 100 can include an external memory controller 116 and platform controller hub 130, which may be configured as a memory controller hub and peripheral controller hub within a system chipset that is in communication with the processor(s) 102.

FIG. 2 is a block diagram of an embodiment of a processor 200 having one or more processor cores 202A-202N, an integrated memory controller 214, and an integrated graphics processor 208. Those elements of FIG. 2 having the same reference numbers (or names) as the elements of any other figure herein can operate or function in any manner similar to that described elsewhere herein, but are not limited to such. Processor 200 can include additional cores up to and including additional core 202N represented by the dashed lined boxes. Each of processor cores 202A-202N includes one or more internal cache units 204A-204N. In some embodiments, each processor core also has access to one or more shared cached units 206.

The internal cache units 204A-204N and shared cache units 206 represent a cache memory hierarchy within the processor 200. The cache memory hierarchy may include at least one level of instruction and data cache within each processor core and one or more levels of shared mid-level cache, such as a Level 2 (L2), Level 3 (L3), Level 4 (L4), or other levels of cache, where the highest level of cache before external memory is classified as the LLC. In some embodiments, cache coherency logic maintains coherency between the various cache units 206 and 204A-204N.

In some embodiments, processor 200 may also include a set of one or more bus controller units 216 and a system agent core 210. The one or more bus controller units 216 manage a set of peripheral buses, such as one or more PCI or PCI express busses. System agent core 210 provides management functionality for the various processor components. In some embodiments, system agent core 210 includes one or more integrated memory controllers 214 to manage access to various external memory devices (not shown).

In some embodiments, one or more of the processor cores 202A-202N include support for simultaneous multi-threading. In such embodiment, the system agent core 210 includes components for coordinating and operating cores 202A-202N during multi-threaded processing. System agent core 210 may additionally include a power control unit (PCU), which includes logic and components to regulate the power state of processor cores 202A-202N and graphics processor 208.

In some embodiments, processor 200 additionally includes graphics processor 208 to execute graphics processing operations. In some embodiments, the graphics processor 208 couples with the set of shared cache units 206, and the system agent core 210, including the one or more integrated memory controllers 214. In some embodiments, the system agent core 210 also includes a display controller 211 to drive graphics processor output to one or more coupled displays. In some embodiments, display controller 211 may also be a separate module coupled with the graphics processor via at least one interconnect, or may be integrated within the graphics processor 208.

In some embodiments, a ring based interconnect unit 212 is used to couple the internal components of the processor 200. However, an alternative interconnect unit may be used, such as a point-to-point interconnect, a switched interconnect, or other techniques, including techniques well known in the art. In some embodiments, graphics processor 208 couples with the ring interconnect 212 via an I/O link 213.

The exemplary I/O link 213 represents at least one of multiple varieties of I/O interconnects, including an on package I/O interconnect which facilitates communication between various processor components and a high-performance embedded memory module 218, such as an eDRAM module. In some embodiments, each of the processor cores 202A-202N and graphics processor 208 use embedded memory modules 218 as a shared Last Level Cache.

In some embodiments, processor cores 202A-202N are homogenous cores executing the same instruction set architecture. In another embodiment, processor cores 202A-202N are heterogeneous in terms of instruction set architecture (ISA), where one or more of processor cores 202A-202N execute a first instruction set, while at least one of the other cores executes a subset of the first instruction set or a different instruction set. In one embodiment processor cores 202A-202N are heterogeneous in terms of microarchitecture, where one or more cores having a relatively higher power consumption couple with one or more power cores having a lower power consumption. Additionally, processor 200 can be implemented on one or more chips or as an SoC integrated circuit having the illustrated components, in addition to other components.

FIG. 3 is a block diagram of a graphics processor 300, which may be a discrete graphics processing unit, or may be a graphics processor integrated with a plurality of processing cores. In some embodiments, the graphics processor communicates via a memory mapped I/O interface to registers on the graphics processor and with commands placed into the processor memory. In some embodiments, graphics processor 300 includes a memory interface 314 to access memory. Memory interface 314 can be an interface to local memory, one or more internal caches, one or more shared external caches, and/or to system memory.

In some embodiments, graphics processor 300 also includes a display controller 302 to drive display output data to a display device 320. Display controller 302 includes hardware for one or more overlay planes for the display and composition of multiple layers of video or user interface elements. The display device 320 can be an internal or external display device. In one embodiment, the display device 320 is a head mounted display device, such as a virtual reality (VR) display device or an augmented reality (AR) display device. In some embodiments, graphics processor 300 includes a video codec engine 306 to encode, decode, or transcode media to, from, or between one or more media encoding formats, including, but not limited to Moving Picture Experts Group (MPEG) formats such as MPEG-2, Advanced Video Coding (AVC) formats such as H.264/MPEG-4 AVC, as well as the Society of Motion Picture & Television Engineers (SMPTE) 421M/VC-1, and Joint Photographic Experts Group (JPEG) formats such as JPEG, and Motion JPEG (MJPEG) formats.

In some embodiments, graphics processor 300 includes a block image transfer (BLIT) engine 304 to perform two-dimensional (2D) rasterizer operations including, for example, bit-boundary block transfers. However, in one embodiment, 2D graphics operations are performed using one or more components of graphics processing engine (GPE) 310. In some embodiments, GPE 310 is a compute engine for performing graphics operations, including three-dimensional (3D) graphics operations and media operations.

In some embodiments, GPE 310 includes a 3D pipeline 312 for performing 3D operations, such as rendering three-dimensional images and scenes using processing functions that act upon 3D primitive shapes (e.g., rectangle, triangle, etc.). The 3D pipeline 312 includes programmable and fixed function elements that perform various tasks within the element and/or spawn execution threads to a 3D/Media sub-system 315. While 3D pipeline 312 can be used to perform media operations, an embodiment of GPE 310 also includes a media pipeline 316 that is specifically used to perform media operations, such as video post-processing and image enhancement.

In some embodiments, media pipeline 316 includes fixed function or programmable logic units to perform one or more specialized media operations, such as video decode acceleration, video de-interlacing, and video encode acceleration in place of, or on behalf of video codec engine 306. In some embodiments, media pipeline 316 additionally includes a thread spawning unit to spawn threads for execution on 3D/Media sub-system 315. The spawned threads perform computations for the media operations on one or more graphics execution units included in 3D/Media sub-system 315.

In some embodiments, 3D/Media subsystem 315 includes logic for executing threads spawned by 3D pipeline 312 and media pipeline 316. In one embodiment, the pipelines send thread execution requests to 3D/Media subsystem 315, which includes thread dispatch logic for arbitrating and dispatching the various requests to available thread execution resources. The execution resources include an array of graphics execution units to process the 3D and media threads. In some embodiments, 3D/Media subsystem 315 includes one or more internal caches for thread instructions and data. In some embodiments, the subsystem also includes shared memory, including registers and addressable memory, to share data between threads and to store output data.

Graphics Processing Engine

FIG. 4 is a block diagram of a graphics processing engine 410 of a graphics processor in accordance with some embodiments. In one embodiment, the graphics processing engine (GPE) 410 is a version of the GPE 310 shown in FIG. 3. Elements of FIG. 4 having the same reference numbers (or names) as the elements of any other figure herein can operate or function in any manner similar to that described elsewhere herein, but are not limited to such. For example, the 3D pipeline 312 and media pipeline 316 of FIG. 3 are illustrated. The media pipeline 316 is optional in some embodiments of the GPE 410 and may not be explicitly included within the GPE 410. For example, and in at least one embodiment, a separate media and/or image processor is coupled to the GPE 410.

In some embodiments, GPE 410 couples with or includes a command streamer 403, which provides a command stream to the 3D pipeline 312 and/or media pipelines 316. In some embodiments, command streamer 403 is coupled with memory, which can be system memory, or one or more of internal cache memory and shared cache memory. In some embodiments, command streamer 403 receives commands from the memory and sends the commands to 3D pipeline 312 and/or media pipeline 316. The commands are directives fetched from a ring buffer, which stores commands for the 3D pipeline 312 and media pipeline 316. In one embodiment, the ring buffer can additionally include batch command buffers storing batches of multiple commands. The commands for the 3D pipeline 312 can also include references to data stored in memory, such as but not limited to vertex and geometry data for the 3D pipeline 312 and/or image data and memory objects for the media pipeline 316. The 3D pipeline 312 and media pipeline 316 process the commands and data by performing operations via logic within the respective pipelines or by dispatching one or more execution threads to a graphics core array 414. In one embodiment, the graphics core array 414 include one or more blocks of graphics cores (e.g., graphics core(s) 415A, graphics core(s) 415B), each block including one or more graphics cores. Each graphics core includes a set of graphics execution resources that includes general-purpose and graphics specific execution logic to perform graphics and compute operations, as well as fixed function texture processing and/or machine learning and artificial intelligence acceleration logic.

In various embodiments, the 3D pipeline 312 includes fixed function and programmable logic to process one or more shader programs, such as vertex shaders, geometry shaders, pixel shaders, fragment shaders, compute shaders, or other shader programs, by processing the instructions and dispatching execution threads to the graphics core array 414. The graphics core array 414 provides a unified block of execution resources for use in processing these shader programs. Multi-purpose execution logic (e.g., execution units) within the graphics core(s) 415A-414B of the graphic core array 414 includes support for various 3D API shader languages and can execute multiple simultaneous execution threads associated with multiple shaders.

In some embodiments, the graphics core array 414 also includes execution logic to perform media functions, such as video and/or image processing. In one embodiment, the execution units additionally include general-purpose logic that is programmable to perform parallel general-purpose computational operations, in addition to graphics processing operations. The general-purpose logic can perform processing operations in parallel or in conjunction with general-purpose logic within the processor core(s) 107 of FIG. 1 or core 202A-202N as in FIG. 2.

Output data generated by threads executing on the graphics core array 414 can output data to memory in a unified return buffer (URB) 418. The URB 418 can store data for multiple threads. In some embodiments, the URB 418 may be used to send data between different threads executing on the graphics core array 414. In some embodiments, the URB 418 may additionally be used for synchronization between threads on the graphics core array and fixed function logic within the shared function logic 420.

In some embodiments, graphics core array 414 is scalable, such that the array includes a variable number of graphics cores, each having a variable number of execution units based on the target power and performance level of GPE 410. In one embodiment, the execution resources are dynamically scalable, such that execution resources may be enabled or disabled as needed.

The graphics core array 414 couples with shared function logic 420 that includes multiple resources that are shared between the graphics cores in the graphics core array. The shared functions within the shared function logic 420 are hardware logic units that provide specialized supplemental functionality to the graphics core array 414. In various embodiments, shared function logic 420 includes but is not limited to sampler 421, math 422, and inter-thread communication (ITC) 423 logic. Additionally, some embodiments implement one or more cache(s) 425 within the shared function logic 420.

A shared function is implemented where the demand for a given specialized function is insufficient for inclusion within the graphics core array 414. Instead a single instantiation of that specialized function is implemented as a stand-alone entity in the shared function logic 420 and shared among the execution resources within the graphics core array 414. The precise set of functions that are shared between the graphics core array 414 and included within the graphics core array 414 varies across embodiments. In some embodiments, specific shared functions within the shared function logic 420 that are used extensively by the graphics core array 414 may be included within shared function logic 416 within the graphics core array 414. In various embodiments, the shared function logic 416 within the graphics core array 414 can include some or all logic within the shared function logic 420. In one embodiment, all logic elements within the shared function logic 420 may be duplicated within the shared function logic 416 of the graphics core array 414. In one embodiment, the shared function logic 420 is excluded in favor of the shared function logic 416 within the graphics core array 414.

FIG. 5 is a block diagram of hardware logic of a graphics processor core 500, according to some embodiments described herein. Elements of FIG. 5 having the same reference numbers (or names) as the elements of any other figure herein can operate or function in any manner similar to that described elsewhere herein, but are not limited to such. The illustrated graphics processor core 500, in some embodiments, is included within the graphics core array 414 of FIG. 4. The graphics processor core 500, sometimes referred to as a core slice, can be one or multiple graphics cores within a modular graphics processor. The graphics processor core 500 is exemplary of one graphics core slice, and a graphics processor as described herein may include multiple graphics core slices based on target power and performance envelopes. Each graphics core 500 can include a fixed function block 530 coupled with multiple sub-cores 501A-501F, also referred to as sub-slices, that include modular blocks of general-purpose and fixed function logic.

In some embodiments, the fixed function block 530 includes a geometry/fixed function pipeline 536 that can be shared by all sub-cores in the graphics processor 500, for example, in lower performance and/or lower power graphics processor implementations. In various embodiments, the geometry/fixed function pipeline 536 includes a 3D fixed function pipeline (e.g., 3D pipeline 312 as in FIG. 3 and FIG. 4) a video front-end unit, a thread spawner and thread dispatcher, and a unified return buffer manager, which manages unified return buffers, such as the unified return buffer 418 of FIG. 4.

In one embodiment, the fixed function block 530 also includes a graphics SoC interface 537, a graphics microcontroller 538, and a media pipeline 539. The graphics SoC interface 537 provides an interface between the graphics core 500 and other processor cores within a system on a chip integrated circuit. The graphics microcontroller 538 is a programmable sub-processor that is configurable to manage various functions of the graphics processor 500, including thread dispatch, scheduling, and pre-emption. The media pipeline 539 (e.g., media pipeline 316 of FIG. 3 and FIG. 4) includes logic to facilitate the decoding, encoding, pre-processing, and/or post-processing of multimedia data, including image and video data. The media pipeline 539 implement media operations via requests to compute or sampling logic within the sub-cores 501-501F.

In one embodiment, the SoC interface 537 enables the graphics core 500 to communicate with general-purpose application processor cores (e.g., CPUs) and/or other components within an SoC, including memory hierarchy elements such as a shared last level cache memory, the system RAM, and/or embedded on-chip or on-package DRAM. The SoC interface 537 can also enable communication with fixed function devices within the SoC, such as camera imaging pipelines, and enables the use of and/or implements global memory atomics that may be shared between the graphics core 500 and CPUs within the SoC. The SoC interface 537 can also implement power management controls for the graphics core 500 and enable an interface between a clock domain of the graphic core 500 and other clock domains within the SoC. In one embodiment, the SoC interface 537 enables receipt of command buffers from a command streamer and global thread dispatcher that are configured to provide commands and instructions to each of one or more graphics cores within a graphics processor. The commands and instructions can be dispatched to the media pipeline 539, when media operations are to be performed, or a geometry and fixed function pipeline (e.g., geometry and fixed function pipeline 536, geometry and fixed function pipeline 514) when graphics processing operations are to be performed.

The graphics microcontroller 538 can be configured to perform various scheduling and management tasks for the graphics core 500. In one embodiment, the graphics microcontroller 538 can perform graphics and/or compute workload scheduling on the various graphics parallel engines within execution unit (EU) arrays 502A-502F, 504A-504F within the sub-cores 501A-501F. In this scheduling model, host software executing on a CPU core of an SoC including the graphics core 500 can submit workloads one of multiple graphic processor doorbells, which invokes a scheduling operation on the appropriate graphics engine. Scheduling operations include determining which workload to run next, submitting a workload to a command streamer, pre-empting existing workloads running on an engine, monitoring progress of a workload, and notifying host software when a workload is complete. In one embodiment, the graphics microcontroller 538 can also facilitate low-power or idle states for the graphics core 500, providing the graphics core 500 with the ability to save and restore registers within the graphics core 500 across low-power state transitions independently from the operating system and/or graphics driver software on the system.

The graphics core 500 may have greater than or fewer than the illustrated sub-cores 501A-501F, up to N modular sub-cores. For each set of N sub-cores, the graphics core 500 can also include shared function logic 510, shared and/or cache memory 512, a geometry/fixed function pipeline 514, as well as additional fixed function logic 516 to accelerate various graphics and compute processing operations. The shared function logic 510 can include logic units associated with the shared function logic 420 of FIG. 4 (e.g., sampler, math, and/or inter-thread communication logic) that can be shared by each N sub-cores within the graphics core 500. The shared and/or cache memory 512 can be a last-level cache for the set of N sub-cores 501A-501F within the graphics core 500, and can also serve as shared memory that is accessible by multiple sub-cores. The geometry/fixed function pipeline 514 can be included instead of the geometry/fixed function pipeline 536 within the fixed function block 530 and can include the same or similar logic units.

In one embodiment, the graphics core 500 includes additional fixed function logic 516 that can include various fixed function acceleration logic for use by the graphics core 500. In one embodiment, the additional fixed function logic 516 includes an additional geometry pipeline for use in position only shading. In position-only shading, two geometry pipelines exist, the full geometry pipeline within the geometry/fixed function pipeline 516, 536, and a cull pipeline, which is an additional geometry pipeline which may be included within the additional fixed function logic 516. In one embodiment, the cull pipeline is a trimmed down version of the full geometry pipeline. The full pipeline and the cull pipeline can execute different instances of the same application, each instance having a separate context. Position only shading can hide long cull runs of discarded triangles, enabling shading to be completed earlier in some instances. For example, and in one embodiment the cull pipeline logic within the additional fixed function logic 516 can execute position shaders in parallel with the main application and generally generates critical results faster than the full pipeline, as the cull pipeline fetches and shades only the position attribute of the vertices, without performing rasterization and rendering of the pixels to the frame buffer. The cull pipeline can use the generated critical results to compute visibility information for all the triangles without regard to whether those triangles are culled. The full pipeline (which in this instance may be referred to as a replay pipeline) can consume the visibility information to skip the culled triangles to shade only the visible triangles that are finally passed to the rasterization phase.

In one embodiment, the additional fixed function logic 516 can also include machine-learning acceleration logic, such as fixed function matrix multiplication logic, for implementations including optimizations for machine learning training or inferencing.

Within each graphics sub-core 501A-501F includes a set of execution resources that may be used to perform graphics, media, and compute operations in response to requests by graphics pipeline, media pipeline, or shader programs. The graphics sub-cores 501A-501F include multiple EU arrays 502A-502F, 504A-504F, thread dispatch and inter-thread communication (TD/IC) logic 503A-503F, a 3D (e.g., texture) sampler 505A-505F, a media sampler 506A-506F, a shader processor 507A-507F, and shared local memory (SLM) 508A-508F. The EU arrays 502A-502F, 504A-504F each include multiple execution units, which are general-purpose graphics processing units capable of performing floating-point and integer/fixed-point logic operations in service of a graphics, media, or compute operation, including graphics, media, or compute shader programs. The TD/IC logic 503A-503F performs local thread dispatch and thread control operations for the execution units within a sub-core and facilitate communication between threads executing on the execution units of the sub-core. The 3D sampler 505A-505F can read texture or other 3D graphics related data into memory. The 3D sampler can read texture data differently based on a configured sample state and the texture format associated with a given texture. The media sampler 506A-506F can perform similar read operations based on the type and format associated with media data. In one embodiment, each graphics sub-core 501A-501F can alternately include a unified 3D and media sampler. Threads executing on the execution units within each of the sub-cores 501A-501F can make use of shared local memory 508A-508F within each sub-core, to enable threads executing within a thread group to execute using a common pool of on-chip memory.

Execution Units

FIGS. 6A-6B illustrate thread execution logic 600 including an array of processing elements employed in a graphics processor core according to embodiments described herein. Elements of FIGS. 6A-6B having the same reference numbers (or names) as the elements of any other figure herein can operate or function in any manner similar to that described elsewhere herein, but are not limited to such. FIG. 6A illustrates an overview of thread execution logic 600, which can include a variant of the hardware logic illustrated with each sub-core 501A-501F of FIG. 5. FIG. 6B illustrates exemplary internal details of an execution unit.

As illustrated in FIG. 6A, in some embodiments thread execution logic 600 includes a shader processor 602, a thread dispatcher 604, instruction cache 606, a scalable execution unit array including a plurality of execution units 608A-608N, a sampler 610, a data cache 612, and a data port 614. In one embodiment, the scalable execution unit array can dynamically scale by enabling or disabling one or more execution units (e.g., any of execution unit 608A, 608B, 608C, 608D, through 608N-1 and 608N) based on the computational requirements of a workload. In one embodiment, the included components are interconnected via an interconnect fabric that links to each of the components. In some embodiments, thread execution logic 600 includes one or more connections to memory, such as system memory or cache memory, through one or more of instruction cache 606, data port 614, sampler 610, and execution units 608A-608N. In some embodiments, each execution unit (e.g. 608A) is a stand-alone programmable general-purpose computational unit that is capable of executing multiple simultaneous hardware threads while processing multiple data elements in parallel for each thread. In various embodiments, the array of execution units 608A-608N is scalable to include any number individual execution units.

In some embodiments, the execution units 608A-608N are primarily used to execute shader programs. A shader processor 602 can process the various shader programs and dispatch execution threads associated with the shader programs via a thread dispatcher 604. In one embodiment, the thread dispatcher includes logic to arbitrate thread initiation requests from the graphics and media pipelines and instantiate the requested threads on one or more execution unit in the execution units 608A-608N. For example, a geometry pipeline can dispatch vertex, tessellation, or geometry shaders to the thread execution logic for processing. In some embodiments, thread dispatcher 604 can also process runtime thread spawning requests from the executing shader programs.

In some embodiments, the execution units 608A-608N support an instruction set that includes native support for many standard 3D graphics shader instructions, such that shader programs from graphics libraries (e.g., Direct 3D and OpenGL) are executed with a minimal translation. The execution units support vertex and geometry processing (e.g., vertex programs, geometry programs, vertex shaders), pixel processing (e.g., pixel shaders, fragment shaders) and general-purpose processing (e.g., compute and media shaders). Each of the execution units 608A-608N is capable of multi-issue single instruction multiple data (SIMD) execution and multi-threaded operation enables an efficient execution environment in the face of higher latency memory accesses. Each hardware thread within each execution unit has a dedicated high-bandwidth register file and associated independent thread-state. Execution is multi-issue per clock to pipelines capable of integer, single and double precision floating point operations, SIMD branch capability, logical operations, transcendental operations, and other miscellaneous operations. While waiting for data from memory or one of the shared functions, dependency logic within the execution units 608A-608N causes a waiting thread to sleep until the requested data has been returned. While the waiting thread is sleeping, hardware resources may be devoted to processing other threads. For example, during a delay associated with a vertex shader operation, an execution unit can perform operations for a pixel shader, fragment shader, or another type of shader program, including a different vertex shader.

Each execution unit in execution units 608A-608N operates on arrays of data elements. The number of data elements is the “execution size,” or the number of channels for the instruction. An execution channel is a logical unit of execution for data element access, masking, and flow control within instructions. The number of channels may be independent of the number of physical Arithmetic Logic Units (ALUs) or Floating Point Units (FPUs) for a particular graphics processor. In some embodiments, execution units 608A-608N support integer and floating-point data types.

The execution unit instruction set includes SIMD instructions. The various data elements can be stored as a packed data type in a register and the execution unit will process the various elements based on the data size of the elements. For example, when operating on a 256-bit wide vector, the 256 bits of the vector are stored in a register and the execution unit operates on the vector as four separate 64-bit packed data elements (Quad-Word (QW) size data elements), eight separate 32-bit packed data elements (Double Word (DW) size data elements), sixteen separate 16-bit packed data elements (Word (W) size data elements), or thirty-two separate 8-bit data elements (byte (B) size data elements). However, different vector widths and register sizes are possible.

In one embodiment one or more execution units can be combined into a fused execution unit 609A-609N having thread control logic (607A-607N) that is common to the fused EUs. Multiple EUs can be fused into an EU group. Each EU in the fused EU group can be configured to execute a separate SIMD hardware thread. The number of EUs in a fused EU group can vary according to embodiments. Additionally, various SIMD widths can be performed per-EU, including but not limited to SIMD8, SIMD16, and SIMD32. Each fused graphics execution unit 609A-609N includes at least two execution units. For example, fused execution unit 609A includes a first EU 608A, second EU 608B, and thread control logic 607A that is common to the first EU 608A and the second EU 608B. The thread control logic 607A controls threads executed on the fused graphics execution unit 609A, allowing each EU within the fused execution units 609A-609N to execute using a common instruction pointer register.

One or more internal instruction caches (e.g., 606) are included in the thread execution logic 600 to cache thread instructions for the execution units. In some embodiments, one or more data caches (e.g., 612) are included to cache thread data during thread execution. In some embodiments, a sampler 610 is included to provide texture sampling for 3D operations and media sampling for media operations. In some embodiments, sampler 610 includes specialized texture or media sampling functionality to process texture or media data during the sampling process before providing the sampled data to an execution unit.

During execution, the graphics and media pipelines send thread initiation requests to thread execution logic 600 via thread spawning and dispatch logic. Once a group of geometric objects has been processed and rasterized into pixel data, pixel processor logic (e.g., pixel shader logic, fragment shader logic, etc.) within the shader processor 602 is invoked to further compute output information and cause results to be written to output surfaces (e.g., color buffers, depth buffers, stencil buffers, etc.). In some embodiments, a pixel shader or fragment shader calculates the values of the various vertex attributes that are to be interpolated across the rasterized object. In some embodiments, pixel processor logic within the shader processor 602 then executes an application programming interface (API)-supplied pixel or fragment shader program. To execute the shader program, the shader processor 602 dispatches threads to an execution unit (e.g., 608A) via thread dispatcher 604. In some embodiments, shader processor 602 uses texture sampling logic in the sampler 610 to access texture data in texture maps stored in memory. Arithmetic operations on the texture data and the input geometry data compute pixel color data for each geometric fragment, or discards one or more pixels from further processing.

In some embodiments, the data port 614 provides a memory access mechanism for the thread execution logic 600 to output processed data to memory for further processing on a graphics processor output pipeline. In some embodiments, the data port 614 includes or couples to one or more cache memories (e.g., data cache 612) to cache data for memory access via the data port.

As illustrated in FIG. 6B, a graphics execution unit 608 can include an instruction fetch unit 637, a general register file array (GRF) 624, an architectural register file array (ARF) 626, a thread arbiter 622, a send unit 630, a branch unit 632, a set of SIMD floating point units (FPUs) 634, and in one embodiment a set of dedicated integer SIMD ALUs 635. The GRF 624 and ARF 626 includes the set of general register files and architecture register files associated with each simultaneous hardware thread that may be active in the graphics execution unit 608. In one embodiment, per thread architectural state is maintained in the ARF 626, while data used during thread execution is stored in the GRF 624. The execution state of each thread, including the instruction pointers for each thread, can be held in thread-specific registers in the ARF 626.

In one embodiment, the graphics execution unit 608 has an architecture that is a combination of Simultaneous Multi-Threading (SMT) and fine-grained Interleaved Multi-Threading (IMT). The architecture has a modular configuration that can be fine-tuned at design time based on a target number of simultaneous threads and number of registers per execution unit, where execution unit resources are divided across logic used to execute multiple simultaneous threads.

In one embodiment, the graphics execution unit 608 can co-issue multiple instructions, which may each be different instructions. The thread arbiter 622 of the graphics execution unit thread 608 can dispatch the instructions to one of the send unit 630, branch unit 642, or SIMD FPU(s) 634 for execution. Each execution thread can access 128 general-purpose registers within the GRF 624, where each register can store 32 bytes, accessible as a SIMD 8-element vector of 32-bit data elements. In one embodiment, each execution unit thread has access to 4 Kbytes within the GRF 624, although embodiments are not so limited, and greater or fewer register resources may be provided in other embodiments. In one embodiment, up to seven threads can execute simultaneously, although the number of threads per execution unit can also vary according to embodiments. In an embodiment in which seven threads may access 4 Kbytes, the GRF 624 can store a total of 28 Kbytes. Flexible addressing modes can permit registers to be addressed together to build effectively wider registers or to represent strided rectangular block data structures.

In one embodiment, memory operations, sampler operations, and other longer-latency system communications are dispatched via “send” instructions that are executed by the message passing send unit 630. In one embodiment, branch instructions are dispatched to a dedicated branch unit 632 to facilitate SIMD divergence and eventual convergence.

In one embodiment, the graphics execution unit 608 includes one or more SIMD floating point units (FPU(s)) 634 to perform floating-point operations. In one embodiment, the FPU(s) 634 also support integer computation. In one embodiment, the FPU(s) 634 can SIMD execute up to M number of 32-bit floating-point (or integer) operations, or SIMD execute up to 2M 16-bit integer or 16-bit floating-point operations. In one embodiment, at least one of the FPU(s) provides extended math capability to support high-throughput transcendental math functions and double precision 64-bit floating-point. In some embodiments, a set of 8-bit integer SIMD ALUs 635 are also present, and may be specifically optimized to perform operations associated with machine learning computations.

In one embodiment, arrays of multiple instances of the graphics execution unit 608 can be instantiated in a graphics sub-core grouping (e.g., a sub-slice). For scalability, product architects can choose the exact number of execution units per sub-core grouping. In one embodiment, the execution unit 608 can execute instructions across a plurality of execution channels. In a further embodiment, each thread executed on the graphics execution unit 608 is executed on a different channel.

FIG. 7 is a block diagram illustrating a graphics processor instruction formats 700 according to some embodiments. In one or more embodiment, the graphics processor execution units support an instruction set having instructions in multiple formats. The solid lined boxes illustrate the components that are generally included in an execution unit instruction, while the dashed lines include components that are optional or that are only included in a sub-set of the instructions. In some embodiments, instruction format 700 described and illustrated are macro-instructions, in that they are instructions supplied to the execution unit, as opposed to micro-operations resulting from instruction decode once the instruction is processed.

In some embodiments, the graphics processor execution units natively support instructions in a 128-bit instruction format 710. A 64-bit compacted instruction format 730 is available for some instructions based on the selected instruction, instruction options, and number of operands. The native 128-bit instruction format 710 provides access to all instruction options, while some options and operations are restricted in the 64-bit format 730. The native instructions available in the 64-bit format 730 vary by embodiment. In some embodiments, the instruction is compacted in part using a set of index values in an index field 713. The execution unit hardware references a set of compaction tables based on the index values and uses the compaction table outputs to reconstruct a native instruction in the 128-bit instruction format 710.

For each format, instruction opcode 712 defines the operation that the execution unit is to perform. The execution units execute each instruction in parallel across the multiple data elements of each operand. For example, in response to an add instruction the execution unit performs a simultaneous add operation across each color channel representing a texture element or picture element. By default, the execution unit performs each instruction across all data channels of the operands. In some embodiments, instruction control field 714 enables control over certain execution options, such as channels selection (e.g., predication) and data channel order (e.g., swizzle). For instructions in the 128-bit instruction format 710 an exec-size field 716 limits the number of data channels that will be executed in parallel. In some embodiments, exec-size field 716 is not available for use in the 64-bit compact instruction format 730.

Some execution unit instructions have up to three operands including two source operands, src0 720, src1 722, and one destination 718. In some embodiments, the execution units support dual destination instructions, where one of the destinations is implied. Data manipulation instructions can have a third source operand (e.g., SRC2 724), where the instruction opcode 712 determines the number of source operands. An instruction's last source operand can be an immediate (e.g., hard-coded) value passed with the instruction.

In some embodiments, the 128-bit instruction format 710 includes an access/address mode field 726 specifying, for example, whether direct register addressing mode or indirect register addressing mode is used. When direct register addressing mode is used, the register address of one or more operands is directly provided by bits in the instruction.

In some embodiments, the 128-bit instruction format 710 includes an access/address mode field 726, which specifies an address mode and/or an access mode for the instruction. In one embodiment, the access mode is used to define a data access alignment for the instruction. Some embodiments support access modes including a 16-byte aligned access mode and a 1-byte aligned access mode, where the byte alignment of the access mode determines the access alignment of the instruction operands. For example, when in a first mode, the instruction may use byte-aligned addressing for source and destination operands and when in a second mode, the instruction may use 16-byte-aligned addressing for all source and destination operands.

In one embodiment, the address mode portion of the access/address mode field 726 determines whether the instruction is to use direct or indirect addressing. When direct register addressing mode is used bits in the instruction directly provide the register address of one or more operands. When indirect register addressing mode is used, the register address of one or more operands may be computed based on an address register value and an address immediate field in the instruction.

In some embodiments instructions are grouped based on opcode 712 bit-fields to simplify Opcode decode 740. For an 8-bit opcode, bits 4, 5, and 6 allow the execution unit to determine the type of opcode. The precise opcode grouping shown is merely an example. In some embodiments, a move and logic opcode group 742 includes data movement and logic instructions (e.g., move (mov), compare (cmp)). In some embodiments, move and logic group 742 shares the five most significant bits (MSB), where move (mov) instructions are in the form of 0000xxxxb and logic instructions are in the form of 0001xxxxb. A flow control instruction group 744 (e.g., call, jump (jmp)) includes instructions in the form of 0010xxxxb (e.g., 0x20). A miscellaneous instruction group 746 includes a mix of instructions, including synchronization instructions (e.g., wait, send) in the form of 0011xxxxb (e.g., 0x30). A parallel math instruction group 748 includes component-wise arithmetic instructions (e.g., add, multiply (mul)) in the form of 0100xxxxb (e.g., 0x40). The parallel math group 748 performs the arithmetic operations in parallel across data channels. The vector math group 750 includes arithmetic instructions (e.g., dp4) in the form of 0101xxxxb (e.g., 0x50). The vector math group performs arithmetic such as dot product calculations on vector operands.

Graphics Pipeline

FIG. 8 is a block diagram of another embodiment of a graphics processor 800. Elements of FIG. 8 having the same reference numbers (or names) as the elements of any other figure herein can operate or function in any manner similar to that described elsewhere herein, but are not limited to such.

In some embodiments, graphics processor 800 includes a geometry pipeline 820, a media pipeline 830, a display engine 840, thread execution logic 850, and a render output pipeline 870. In some embodiments, graphics processor 800 is a graphics processor within a multi-core processing system that includes one or more general-purpose processing cores. The graphics processor is controlled by register writes to one or more control registers (not shown) or via commands issued to graphics processor 800 via a ring interconnect 802. In some embodiments, ring interconnect 802 couples graphics processor 800 to other processing components, such as other graphics processors or general-purpose processors. Commands from ring interconnect 802 are interpreted by a command streamer 803, which supplies instructions to individual components of the geometry pipeline 820 or the media pipeline 830.

In some embodiments, command streamer 803 directs the operation of a vertex fetcher 805 that reads vertex data from memory and executes vertex-processing commands provided by command streamer 803. In some embodiments, vertex fetcher 805 provides vertex data to a vertex shader 807, which performs coordinate space transformation and lighting operations to each vertex. In some embodiments, vertex fetcher 805 and vertex shader 807 execute vertex-processing instructions by dispatching execution threads to execution units 852A-852B via a thread dispatcher 831.

In some embodiments, execution units 852A-852B are an array of vector processors having an instruction set for performing graphics and media operations. In some embodiments, execution units 852A-852B have an attached L1 cache 851 that is specific for each array or shared between the arrays. The cache can be configured as a data cache, an instruction cache, or a single cache that is partitioned to contain data and instructions in different partitions.

In some embodiments, geometry pipeline 820 includes tessellation components to perform hardware-accelerated tessellation of 3D objects. In some embodiments, a programmable hull shader 811 configures the tessellation operations. A programmable domain shader 817 provides back-end evaluation of tessellation output. A tessellator 813 operates at the direction of hull shader 811 and contains special purpose logic to generate a set of detailed geometric objects based on a coarse geometric model that is provided as input to geometry pipeline 820. In some embodiments, if tessellation is not used, tessellation components (e.g., hull shader 811, tessellator 813, and domain shader 817) can be bypassed.

In some embodiments, complete geometric objects can be processed by a geometry shader 819 via one or more threads dispatched to execution units 852A-852B, or can proceed directly to the clipper 829. In some embodiments, the geometry shader operates on entire geometric objects, rather than vertices or patches of vertices as in previous stages of the graphics pipeline. If the tessellation is disabled the geometry shader 819 receives input from the vertex shader 807. In some embodiments, geometry shader 819 is programmable by a geometry shader program to perform geometry tessellation if the tessellation units are disabled.

Before rasterization, a clipper 829 processes vertex data. The clipper 829 may be a fixed function clipper or a programmable clipper having clipping and geometry shader functions. In some embodiments, a rasterizer and depth test component 873 in the render output pipeline 870 dispatches pixel shaders to convert the geometric objects into per pixel representations. In some embodiments, pixel shader logic is included in thread execution logic 850. In some embodiments, an application can bypass the rasterizer and depth test component 873 and access un-rasterized vertex data via a stream out unit 823.

The graphics processor 800 has an interconnect bus, interconnect fabric, or some other interconnect mechanism that allows data and message passing amongst the major components of the processor. In some embodiments, execution units 852A-852B and associated logic units (e.g., L1 cache 851, sampler 854, texture cache 858, etc.) interconnect via a data port 856 to perform memory access and communicate with render output pipeline components of the processor. In some embodiments, sampler 854, caches 851, 858 and execution units 852A-852B each have separate memory access paths. In one embodiment, the texture cache 858 can also be configured as a sampler cache.

In some embodiments, render output pipeline 870 contains a rasterizer and depth test component 873 that converts vertex-based objects into an associated pixel-based representation. In some embodiments, the rasterizer logic includes a windower/masker unit to perform fixed function triangle and line rasterization. An associated render cache 878 and depth cache 879 are also available in some embodiments. A pixel operations component 877 performs pixel-based operations on the data, though in some instances, pixel operations associated with 2D operations (e.g. bit block image transfers with blending) are performed by the 2D engine 841, or substituted at display time by the display controller 843 using overlay display planes. In some embodiments, a shared L3 cache 875 is available to all graphics components, allowing the sharing of data without the use of main system memory.

In some embodiments, graphics processor media pipeline 830 includes a media engine 837 and a video front-end 834. In some embodiments, video front-end 834 receives pipeline commands from the command streamer 803. In some embodiments, media pipeline 830 includes a separate command streamer. In some embodiments, video front-end 834 processes media commands before sending the command to the media engine 837. In some embodiments, media engine 837 includes thread spawning functionality to spawn threads for dispatch to thread execution logic 850 via thread dispatcher 831.

In some embodiments, graphics processor 800 includes a display engine 840. In some embodiments, display engine 840 is external to processor 800 and couples with the graphics processor via the ring interconnect 802, or some other interconnect bus or fabric. In some embodiments, display engine 840 includes a 2D engine 841 and a display controller 843. In some embodiments, display engine 840 contains special purpose logic capable of operating independently of the 3D pipeline. In some embodiments, display controller 843 couples with a display device (not shown), which may be a system integrated display device, as in a laptop computer, or an external display device attached via a display device connector.

In some embodiments, the geometry pipeline 820 and media pipeline 830 are configurable to perform operations based on multiple graphics and media programming interfaces and are not specific to any one application programming interface (API). In some embodiments, driver software for the graphics processor translates API calls that are specific to a particular graphics or media library into commands that can be processed by the graphics processor. In some embodiments, support is provided for the Open Graphics Library (OpenGL), Open Computing Language (OpenCL), and/or Vulkan graphics and compute API, all from the Khronos Group. In some embodiments, support may also be provided for the Direct3D library from the Microsoft Corporation. In some embodiments, a combination of these libraries may be supported. Support may also be provided for the Open Source Computer Vision Library (OpenCV). A future API with a compatible 3D pipeline would also be supported if a mapping can be made from the pipeline of the future API to the pipeline of the graphics processor.

Graphics Pipeline Programming

FIG. 9A is a block diagram illustrating a graphics processor command format 900 according to some embodiments. FIG. 9B is a block diagram illustrating a graphics processor command sequence 910 according to an embodiment. The solid lined boxes in FIG. 9A illustrate the components that are generally included in a graphics command while the dashed lines include components that are optional or that are only included in a sub-set of the graphics commands. The exemplary graphics processor command format 900 of FIG. 9A includes data fields to identify a client 902, a command operation code (opcode) 904, and data 906 for the command. A sub-opcode 905 and a command size 908 are also included in some commands.

In some embodiments, client 902 specifies the client unit of the graphics device that processes the command data. In some embodiments, a graphics processor command parser examines the client field of each command to condition the further processing of the command and route the command data to the appropriate client unit. In some embodiments, the graphics processor client units include a memory interface unit, a render unit, a 2D unit, a 3D unit, and a media unit. Each client unit has a corresponding processing pipeline that processes the commands. Once the command is received by the client unit, the client unit reads the opcode 904 and, if present, sub-opcode 905 to determine the operation to perform. The client unit performs the command using information in data field 906. For some commands an explicit command size 908 is expected to specify the size of the command. In some embodiments, the command parser automatically determines the size of at least some of the commands based on the command opcode. In some embodiments commands are aligned via multiples of a double word.

The flow diagram in FIG. 9B illustrates an exemplary graphics processor command sequence 910. In some embodiments, software or firmware of a data processing system that features an embodiment of a graphics processor uses a version of the command sequence shown to set up, execute, and terminate a set of graphics operations. A sample command sequence is shown and described for purposes of example only as embodiments are not limited to these specific commands or to this command sequence. Moreover, the commands may be issued as batch of commands in a command sequence, such that the graphics processor will process the sequence of commands in at least partially concurrence.

In some embodiments, the graphics processor command sequence 910 may begin with a pipeline flush command 912 to cause any active graphics pipeline to complete the currently pending commands for the pipeline. In some embodiments, the 3D pipeline 922 and the media pipeline 924 do not operate concurrently. The pipeline flush is performed to cause the active graphics pipeline to complete any pending commands. In response to a pipeline flush, the command parser for the graphics processor will pause command processing until the active drawing engines complete pending operations and the relevant read caches are invalidated. Optionally, any data in the render cache that is marked ‘dirty’ can be flushed to memory. In some embodiments, pipeline flush command 912 can be used for pipeline synchronization or before placing the graphics processor into a low power state.

In some embodiments, a pipeline select command 913 is used when a command sequence requires the graphics processor to explicitly switch between pipelines. In some embodiments, a pipeline select command 913 is required only once within an execution context before issuing pipeline commands unless the context is to issue commands for both pipelines. In some embodiments, a pipeline flush command 912 is required immediately before a pipeline switch via the pipeline select command 913.

In some embodiments, a pipeline control command 914 configures a graphics pipeline for operation and is used to program the 3D pipeline 922 and the media pipeline 924. In some embodiments, pipeline control command 914 configures the pipeline state for the active pipeline. In one embodiment, the pipeline control command 914 is used for pipeline synchronization and to clear data from one or more cache memories within the active pipeline before processing a batch of commands.

In some embodiments, return buffer state commands 916 are used to configure a set of return buffers for the respective pipelines to write data. Some pipeline operations require the allocation, selection, or configuration of one or more return buffers into which the operations write intermediate data during processing. In some embodiments, the graphics processor also uses one or more return buffers to store output data and to perform cross thread communication. In some embodiments, the return buffer state 916 includes selecting the size and number of return buffers to use for a set of pipeline operations.

The remaining commands in the command sequence differ based on the active pipeline for operations. Based on a pipeline determination 920, the command sequence is tailored to the 3D pipeline 922 beginning with the 3D pipeline state 930 or the media pipeline 924 beginning at the media pipeline state 940.

The commands to configure the 3D pipeline state 930 include 3D state setting commands for vertex buffer state, vertex element state, constant color state, depth buffer state, and other state variables that are to be configured before 3D primitive commands are processed. The values of these commands are determined at least in part based on the particular 3D API in use. In some embodiments, 3D pipeline state 930 commands are also able to selectively disable or bypass certain pipeline elements if those elements will not be used.

In some embodiments, 3D primitive 932 command is used to submit 3D primitives to be processed by the 3D pipeline. Commands and associated parameters that are passed to the graphics processor via the 3D primitive 932 command are forwarded to the vertex fetch function in the graphics pipeline. The vertex fetch function uses the 3D primitive 932 command data to generate vertex data structures. The vertex data structures are stored in one or more return buffers. In some embodiments, 3D primitive 932 command is used to perform vertex operations on 3D primitives via vertex shaders. To process vertex shaders, 3D pipeline 922 dispatches shader execution threads to graphics processor execution units.

In some embodiments, 3D pipeline 922 is triggered via an execute 934 command or event. In some embodiments, a register write triggers command execution. In some embodiments execution is triggered via a ‘go’ or ‘kick’ command in the command sequence. In one embodiment, command execution is triggered using a pipeline synchronization command to flush the command sequence through the graphics pipeline. The 3D pipeline will perform geometry processing for the 3D primitives. Once operations are complete, the resulting geometric objects are rasterized and the pixel engine colors the resulting pixels. Additional commands to control pixel shading and pixel back end operations may also be included for those operations.

In some embodiments, the graphics processor command sequence 910 follows the media pipeline 924 path when performing media operations. In general, the specific use and manner of programming for the media pipeline 924 depends on the media or compute operations to be performed. Specific media decode operations may be offloaded to the media pipeline during media decode. In some embodiments, the media pipeline can also be bypassed and media decode can be performed in whole or in part using resources provided by one or more general-purpose processing cores. In one embodiment, the media pipeline also includes elements for general-purpose graphics processor unit (GPGPU) operations, where the graphics processor is used to perform SIMD vector operations using computational shader programs that are not explicitly related to the rendering of graphics primitives.

In some embodiments, media pipeline 924 is configured in a similar manner as the 3D pipeline 922. A set of commands to configure the media pipeline state 940 are dispatched or placed into a command queue before the media object commands 942. In some embodiments, commands for the media pipeline state 940 include data to configure the media pipeline elements that will be used to process the media objects. This includes data to configure the video decode and video encode logic within the media pipeline, such as encode or decode format. In some embodiments, commands for the media pipeline state 940 also support the use of one or more pointers to “indirect” state elements that contain a batch of state settings.

In some embodiments, media object commands 942 supply pointers to media objects for processing by the media pipeline. The media objects include memory buffers containing video data to be processed. In some embodiments, all media pipeline states must be valid before issuing a media object command 942. Once the pipeline state is configured and media object commands 942 are queued, the media pipeline 924 is triggered via an execute command 944 or an equivalent execute event (e.g., register write). Output from media pipeline 924 may then be post processed by operations provided by the 3D pipeline 922 or the media pipeline 924. In some embodiments, GPGPU operations are configured and executed in a similar manner as media operations.

Graphics Software Architecture

FIG. 10 illustrates exemplary graphics software architecture for a data processing system 1000 according to some embodiments. In some embodiments, software architecture includes a 3D graphics application 1010, an operating system 1020, and at least one processor 1030. In some embodiments, processor 1030 includes a graphics processor 1032 and one or more general-purpose processor core(s) 1034. The graphics application 1010 and operating system 1020 each execute in the system memory 1050 of the data processing system.

In some embodiments, 3D graphics application 1010 contains one or more shader programs including shader instructions 1012. The shader language instructions may be in a high-level shader language, such as the High Level Shader Language (HLSL) or the OpenGL Shader Language (GLSL). The application also includes executable instructions 1014 in a machine language suitable for execution by the general-purpose processor core 1034. The application also includes graphics objects 1016 defined by vertex data.

In some embodiments, operating system 1020 is a Microsoft® Windows® operating system from the Microsoft Corporation, a proprietary UNIX-like operating system, or an open source UNIX-like operating system using a variant of the Linux kernel. The operating system 1020 can support a graphics API 1022 such as the Direct3D API, the OpenGL API, or the Vulkan API. When the Direct3D API is in use, the operating system 1020 uses a front-end shader compiler 1024 to compile any shader instructions 1012 in HLSL into a lower-level shader language. The compilation may be a just-in-time (JIT) compilation or the application can perform shader pre-compilation. In some embodiments, high-level shaders are compiled into low-level shaders during the compilation of the 3D graphics application 1010. In some embodiments, the shader instructions 1012 are provided in an intermediate form, such as a version of the Standard Portable Intermediate Representation (SPIR) used by the Vulkan API.

In some embodiments, user mode graphics driver 1026 contains a back-end shader compiler 1027 to convert the shader instructions 1012 into a hardware specific representation. When the OpenGL API is in use, shader instructions 1012 in the GLSL high-level language are passed to a user mode graphics driver 1026 for compilation. In some embodiments, user mode graphics driver 1026 uses operating system kernel mode functions 1028 to communicate with a kernel mode graphics driver 1029. In some embodiments, kernel mode graphics driver 1029 communicates with graphics processor 1032 to dispatch commands and instructions.

IP Core Implementations

One or more aspects of at least one embodiment may be implemented by representative code stored on a machine-readable medium which represents and/or defines logic within an integrated circuit such as a processor. For example, the machine-readable medium may include instructions which represent various logic within the processor. When read by a machine, the instructions may cause the machine to fabricate the logic to perform the techniques described herein. Such representations, known as “IP cores,” are reusable units of logic for an integrated circuit that may be stored on a tangible, machine-readable medium as a hardware model that describes the structure of the integrated circuit. The hardware model may be supplied to various customers or manufacturing facilities, which load the hardware model on fabrication machines that manufacture the integrated circuit. The integrated circuit may be fabricated such that the circuit performs operations described in association with any of the embodiments described herein.

FIG. 11A is a block diagram illustrating an IP core development system 1100 that may be used to manufacture an integrated circuit to perform operations according to an embodiment. The IP core development system 1100 may be used to generate modular, re-usable designs that can be incorporated into a larger design or used to construct an entire integrated circuit (e.g., an SOC integrated circuit). A design facility 1130 can generate a software simulation 1110 of an IP core design in a high-level programming language (e.g., C/C++). The software simulation 1110 can be used to design, test, and verify the behavior of the IP core using a simulation model 1112. The simulation model 1112 may include functional, behavioral, and/or timing simulations. A register transfer level (RTL) design 1115 can then be created or synthesized from the simulation model 1112. The RTL design 1115 is an abstraction of the behavior of the integrated circuit that models the flow of digital signals between hardware registers, including the associated logic performed using the modeled digital signals. In addition to an RTL design 1115, lower-level designs at the logic level or transistor level may also be created, designed, or synthesized. Thus, the particular details of the initial design and simulation may vary.

The RTL design 1115 or equivalent may be further synthesized by the design facility into a hardware model 1120, which may be in a hardware description language (HDL), or some other representation of physical design data. The HDL may be further simulated or tested to verify the IP core design. The IP core design can be stored for delivery to a 3^(rd) party fabrication facility 1165 using non-volatile memory 1140 (e.g., hard disk, flash memory, or any non-volatile storage medium). Alternatively, the IP core design may be transmitted (e.g., via the Internet) over a wired connection 1150 or wireless connection 1160. The fabrication facility 1165 may then fabricate an integrated circuit that is based at least in part on the IP core design. The fabricated integrated circuit can be configured to perform operations in accordance with at least one embodiment described herein.

FIG. 11B illustrates a cross-section side view of an integrated circuit package assembly 1170, according to some embodiments described herein. The integrated circuit package assembly 1170 illustrates an implementation of one or more processor or accelerator devices as described herein. The package assembly 1170 includes multiple units of hardware logic 1172, 1174 connected to a substrate 1180. The logic 1172, 1174 may be implemented at least partly in configurable logic or fixed-functionality logic hardware, and can include one or more portions of any of the processor core(s), graphics processor(s), or other accelerator devices described herein. Each unit of logic 1172, 1174 can be implemented within a semiconductor die and coupled with the substrate 1180 via an interconnect structure 1173. The interconnect structure 1173 may be configured to route electrical signals between the logic 1172, 1174 and the substrate 1180, and can include interconnects such as, but not limited to bumps or pillars. In some embodiments, the interconnect structure 1173 may be configured to route electrical signals such as, for example, input/output (I/O) signals and/or power or ground signals associated with the operation of the logic 1172, 1174. In some embodiments, the substrate 1180 is an epoxy-based laminate substrate. The package substrate 1180 may include other suitable types of substrates in other embodiments. The package assembly 1170 can be connected to other electrical devices via a package interconnect 1183. The package interconnect 1183 may be coupled to a surface of the substrate 1180 to route electrical signals to other electrical devices, such as a motherboard, other chipset, or multi-chip module.

In some embodiments, the units of logic 1172, 1174 are electrically coupled with a bridge 1182 that is configured to route electrical signals between the logic 1172, 1174. The bridge 1182 may be a dense interconnect structure that provides a route for electrical signals. The bridge 1182 may include a bridge substrate composed of glass or a suitable semiconductor material. Electrical routing features can be formed on the bridge substrate to provide a chip-to-chip connection between the logic 1172, 1174.

Although two units of logic 1172, 1174 and a bridge 1182 are illustrated, embodiments described herein may include more or fewer logic units on one or more dies. The one or more dies may be connected by zero or more bridges, as the bridge 1182 may be excluded when the logic is included on a single die. Alternatively, multiple dies or units of logic can be connected by one or more bridges. Additionally, multiple logic units, dies, and bridges can be connected together in other possible configurations, including three-dimensional configurations.

Exemplary System on a Chip Integrated Circuit

FIGS. 12-14 illustrated exemplary integrated circuits and associated graphics processors that may be fabricated using one or more IP cores, according to various embodiments described herein. In addition to what is illustrated, other logic and circuits may be included, including additional graphics processors/cores, peripheral interface controllers, or general-purpose processor cores.

FIG. 12 is a block diagram illustrating an exemplary system on a chip integrated circuit 1200 that may be fabricated using one or more IP cores, according to an embodiment. Exemplary integrated circuit 1200 includes one or more application processor(s) 1205 (e.g., CPUs), at least one graphics processor 1210, and may additionally include an image processor 1215 and/or a video processor 1220, any of which may be a modular IP core from the same or multiple different design facilities. Integrated circuit 1200 includes peripheral or bus logic including a USB controller 1225, UART controller 1230, an SPI/SDIO controller 1235, and an I²S/I²C controller 1240. Additionally, the integrated circuit can include a display device 1245 coupled to one or more of a high-definition multimedia interface (HDMI) controller 1250 and a mobile industry processor interface (MIPI) display interface 1255. Storage may be provided by a flash memory subsystem 1260 including flash memory and a flash memory controller. Memory interface may be provided via a memory controller 1265 for access to SDRAM or SRAM memory devices. Some integrated circuits additionally include an embedded security engine 1270.

FIGS. 13A-13B are block diagrams illustrating exemplary graphics processors for use within an SoC, according to embodiments described herein. FIG. 13A illustrates an exemplary graphics processor 1310 of a system on a chip integrated circuit that may be fabricated using one or more IP cores, according to an embodiment. FIG. 13B illustrates an additional exemplary graphics processor 1340 of a system on a chip integrated circuit that may be fabricated using one or more IP cores, according to an embodiment. Graphics processor 1310 of FIG. 13A is an example of a low power graphics processor core. Graphics processor 1340 of FIG. 13B is an example of a higher performance graphics processor core. Each of the graphics processors 1310, 1340 can be variants of the graphics processor 1210 of FIG. 12.

As shown in FIG. 13A, graphics processor 1310 includes a vertex processor 1305 and one or more fragment processor(s) 1315A-1315N (e.g., 1315A, 1315B, 1315C, 1315D, through 1315N-1, and 1315N). Graphics processor 1310 can execute different shader programs via separate logic, such that the vertex processor 1305 is optimized to execute operations for vertex shader programs, while the one or more fragment processor(s) 1315A-1315N execute fragment (e.g., pixel) shading operations for fragment or pixel shader programs. The vertex processor 1305 performs the vertex processing stage of the 3D graphics pipeline and generates primitives and vertex data. The fragment processor(s) 1315A-1315N use the primitive and vertex data generated by the vertex processor 1305 to produce a framebuffer that is displayed on a display device. In one embodiment, the fragment processor(s) 1315A-1315N are optimized to execute fragment shader programs as provided for in the OpenGL API, which may be used to perform similar operations as a pixel shader program as provided for in the Direct 3D API.

Graphics processor 1310 additionally includes one or more memory management units (MMUs) 1320A-1320B, cache(s) 1325A-1325B, and circuit interconnect(s) 1330A-1330B. The one or more MMU(s) 1320A-1320B provide for virtual to physical address mapping for the graphics processor 1310, including for the vertex processor 1305 and/or fragment processor(s) 1315A-1315N, which may reference vertex or image/texture data stored in memory, in addition to vertex or image/texture data stored in the one or more cache(s) 1325A-1325B. In one embodiment, the one or more MMU(s) 1320A-1320B may be synchronized with other MMUs within the system, including one or more MMUs associated with the one or more application processor(s) 1205, image processor 1215, and/or video processor 1220 of FIG. 12, such that each processor 1205-1220 can participate in a shared or unified virtual memory system. The one or more circuit interconnect(s) 1330A-1330B enable graphics processor 1310 to interface with other IP cores within the SoC, either via an internal bus of the SoC or via a direct connection, according to embodiments.

As shown FIG. 13B, graphics processor 1340 includes the one or more MMU(s) 1320A-1320B, caches 1325A-1325B, and circuit interconnects 1330A-1330B of the graphics processor 1310 of FIG. 13A. Graphics processor 1340 includes one or more shader core(s) 1355A-1355N (e.g., 1455A, 1355B, 1355C, 1355D, 1355E, 1355F, through 1355N-1, and 1355N), which provides for a unified shader core architecture in which a single core or type or core can execute all types of programmable shader code, including shader program code to implement vertex shaders, fragment shaders, and/or compute shaders. The exact number of shader cores present can vary among embodiments and implementations. Additionally, graphics processor 1340 includes an inter-core task manager 1345, which acts as a thread dispatcher to dispatch execution threads to one or more shader cores 1355A-1355N and a tiling unit 1358 to accelerate tiling operations for tile-based rendering, in which rendering operations for a scene are subdivided in image space, for example to exploit local spatial coherence within a scene or to optimize use of internal caches.

FIGS. 14A-14B illustrate additional exemplary graphics processor logic according to embodiments described herein. FIG. 14A illustrates a graphics core 1400 that may be included within the graphics processor 1210 of FIG. 12, and may be a unified shader core 1355A-1355N as in FIG. 13B. FIG. 14B illustrates a highly-parallel general-purpose graphics processing unit 1430 suitable for deployment on a multi-chip module.

As shown in FIG. 14A, the graphics core 1400 includes a shared instruction cache 1402, a texture unit 1418, and a cache/shared memory 1420 that are common to the execution resources within the graphics core 1400. The graphics core 1400 can include multiple slices 1401A-1401N or partition for each core, and a graphics processor can include multiple instances of the graphics core 1400. The slices 1401A-1401N can include support logic including a local instruction cache 1404A-1404N, a thread scheduler 1406A-1406N, a thread dispatcher 1408A-1408N, and a set of registers 1410A. To perform logic operations, the slices 1401A-1401N can include a set of additional function units (AFUs 1412A-1412N), floating-point units (FPU 1414A-1414N), integer arithmetic logic units (ALUs 1416-1416N), address computational units (ACU 1413A-1413N), double-precision floating-point units (DPFPU 1415A-1415N), and matrix processing units (MPU 1417A-1417N).

Some of the computational units operate at a specific precision. For example, the FPUs 1414A-1414N can perform single-precision (32-bit) and half-precision (16-bit) floating point operations, while the DPFPUs 1415A-1415N perform double precision (64-bit) floating point operations. The ALUs 1416A-1416N can perform variable precision integer operations at 8-bit, 16-bit, and 32-bit precision, and can be configured for mixed precision operations. The MPUs 1417A-1417N can also be configured for mixed precision matrix operations, including half-precision floating point and 8-bit integer operations. The MPUs 1417-1417N can perform a variety of matrix operations to accelerate machine learning application frameworks, including enabling support for accelerated general matrix to matrix multiplication (GEMM). The AFUs 1412A-1412N can perform additional logic operations not supported by the floating-point or integer units, including trigonometric operations (e.g., Sine, Cosine, etc.).

As shown in FIG. 14B, a general-purpose processing unit (GPGPU) 1430 can be configured to enable highly-parallel compute operations to be performed by an array of graphics processing units. Additionally, the GPGPU 1430 can be linked directly to other instances of the GPGPU to create a multi-GPU cluster to improve training speed for particularly deep neural networks. The GPGPU 1430 includes a host interface 1432 to enable a connection with a host processor. In one embodiment, the host interface 1432 is a PCI Express interface. However, the host interface can also be a vendor specific communications interface or communications fabric. The GPGPU 1430 receives commands from the host processor and uses a global scheduler 1434 to distribute execution threads associated with those commands to a set of compute clusters 1436A-1436H. The compute clusters 1436A-1436H share a cache memory 1438. The cache memory 1438 can serve as a higher-level cache for cache memories within the compute clusters 1436A-1436H.

The GPGPU 1430 includes memory 1434A-1434B coupled with the compute clusters 1436A-1436H via a set of memory controllers 1442A-1442B. In various embodiments, the memory 1434A-1434B can include various types of memory devices including dynamic random-access memory (DRAM) or graphics random access memory, such as synchronous graphics random access memory (SGRAM), including graphics double data rate (GDDR) memory.

In one embodiment, the compute clusters 1436A-1436H each include a set of graphics cores, such as the graphics core 1400 of FIG. 14A, which can include multiple types of integer and floating point logic units that can perform computational operations at a range of precisions including suited for machine learning computations. For example, and in one embodiment at least a subset of the floating point units in each of the compute clusters 1436A-1436H can be configured to perform 16-bit or 32-bit floating point operations, while a different subset of the floating point units can be configured to perform 64-bit floating point operations.

Multiple instances of the GPGPU 1430 can be configured to operate as a compute cluster. The communication mechanism used by the compute cluster for synchronization and data exchange varies across embodiments. In one embodiment, the multiple instances of the GPGPU 1430 communicate over the host interface 1432. In one embodiment, the GPGPU 1430 includes an I/O hub 1439 that couples the GPGPU 1430 with a GPU link 1440 that enables a direct connection to other instances of the GPGPU. In one embodiment, the GPU link 1440 is coupled to a dedicated GPU-to-GPU bridge that enables communication and synchronization between multiple instances of the GPGPU 1430. In one embodiment, the GPU link 1440 couples with a high speed interconnect to transmit and receive data to other GPGPUs or parallel processors. In one embodiment, the multiple instances of the GPGPU 1430 are located in separate data processing systems and communicate via a network device that is accessible via the host interface 1432. In one embodiment, the GPU link 1440 can be configured to enable a connection to a host processor in addition to or as an alternative to the host interface 1432.

While the illustrated configuration of the GPGPU 1430 can be configured to train neural networks, one embodiment provides alternate configuration of the GPGPU 1430 that can be configured for deployment within a high performance or low power inferencing platform. In an inferencing configuration, the GPGPU 1430 includes fewer of the compute clusters 1436A-1436H relative to the training configuration. Additionally, the memory technology associated with the memory 1434A-1434B may differ between inferencing and training configurations, with higher bandwidth memory technologies devoted to training configurations. In one embodiment, the inferencing configuration of the GPGPU 1430 can support inferencing specific instructions. For example, an inferencing configuration can provide support for one or more 8-bit integer dot product instructions, which are commonly used during inferencing operations for deployed neural networks.

FIG. 15 illustrates a computing device 1500 hosting a smart spill/fill mechanism (“spill/fill mechanism”) 1510 according to one embodiment. Computing device 1500 represents a communication and data processing device including (but not limited to) smart wearable devices, smartphones, virtual reality (VR) devices, head-mounted display (HMDs), mobile computers, Internet of Things (IoT) devices, laptop computers, desktop computers, server computers, etc., and be similar to or the same as computing device 100 of FIG. 1; accordingly, for brevity, clarity, and ease of understanding, many of the details stated above with reference to FIGS. 1-14 are not further discussed or repeated hereafter.

Computing device 1500 may further include (without limitations) an autonomous machine or an artificially intelligent agent, such as a mechanical agent or machine, an electronics agent or machine, a virtual agent or machine, an electro-mechanical agent or machine, etc. Examples of autonomous machines or artificially intelligent agents may include (without limitation) robots, autonomous vehicles (e.g., self-driving cars, self-flying planes, self-sailing boats, etc.), autonomous equipment (self-operating construction vehicles, self-operating medical equipment, etc.), and/or the like. Throughout this document, “computing device” may be interchangeably referred to as “autonomous machine” or “artificially intelligent agent” or simply “robot”.

It contemplated that although “autonomous vehicle” and “autonomous driving” are referenced throughout this document, embodiments are not limited as such. For example, “autonomous vehicle” is not limed to an automobile but that it may include any number and type of autonomous machines, such as robots, autonomous equipment, household autonomous devices, and/or the like, and any one or more tasks or operations relating to such autonomous machines may be interchangeably referenced with autonomous driving.

Computing device 1500 may further include (without limitations) large computing systems, such as server computers, desktop computers, etc., and may further include set-top boxes (e.g., Internet-based cable television set-top boxes, etc.), global positioning system (GPS)-based devices, etc. Computing device 1500 may include mobile computing devices serving as communication devices, such as cellular phones including smartphones, personal digital assistants (PDAs), tablet computers, laptop computers, e-readers, smart televisions, television platforms, wearable devices (e.g., glasses, watches, bracelets, smartcards, jewelry, clothing items, etc.), media players, etc. For example, in one embodiment, computing device 1500 may include a mobile computing device employing a computer platform hosting an integrated circuit (“IC”), such as system on a chip (“SoC” or “SOC”), integrating various hardware and/or software components of computing device 1500 on a single chip.

As illustrated, in one embodiment, computing device 1500 may include any number and type of hardware and/or software components, such as (without limitation) graphics processing unit (“GPU” or simply “graphics processor”) 1514, graphics driver (also referred to as “GPU driver”, “graphics driver logic”, “driver logic”, user-mode driver (UMD), UMD, user-mode driver framework (UMDF), UMDF, or simply “driver”) 1516, central processing unit (“CPU” or simply “application processor”) 1512, memory 1508, network devices, drivers, or the like, as well as input/output (I/O) sources 1504, such as touchscreens, touch panels, touch pads, virtual or regular keyboards, virtual or regular mice, ports, connectors, etc. Computing device 1500 may include operating system (OS) 1506 serving as an interface between hardware and/or physical resources of the computer device 1500 and a user. It is contemplated that graphics processor 1514 and application processor 1512 may be one or more of processor(s) 102 of FIG. 1.

It is to be appreciated that a lesser or more equipped system than the example described above may be preferred for certain implementations. Therefore, the configuration of computing device 1500 may vary from implementation to implementation depending upon numerous factors, such as price constraints, performance requirements, technological improvements, or other circumstances.

Embodiments may be implemented as any or a combination of: one or more microchips or integrated circuits interconnected using a parentboard, hardwired logic, software stored by a memory device and executed by a microprocessor, firmware, an application specific integrated circuit (ASIC), and/or a field programmable gate array (FPGA). The terms “logic”, “module”, “component”, “engine”, and “mechanism” may include, by way of example, software or hardware and/or combinations of software and hardware.

In one embodiment, as illustrated, spill/fill mechanism 1510 may be hosted by graphics driver 1516. In another embodiment, spill/fill mechanism 1510 may be hosted or facilitated by operating system 1506 of computing device 1500. In yet another embodiment, spill/fill mechanism 1510 may be hosted by or part of graphics processing unit (“GPU” or simply graphics processor”) 1514 or firmware of graphics processor 1514. For example, spill/fill mechanism 1510 may be embedded in or implemented as part of the processing hardware of graphics processor 1514. Similarly, in yet another embodiment, spill/fill mechanism 1510 may be hosted by or part of central processing unit (“CPU” or simply “application processor”) 1512. For example, spill/fill mechanism 1510 may be embedded in or implemented as part of the processing hardware of application processor 1512.

In yet another embodiment, spill/fill mechanism 1510 may be hosted by or part of any number and type of components of computing device 1500, such as a portion of spill/fill mechanism 1510 may be hosted by or part of operating system 1506, another portion may be hosted by or part of graphics processor 1514, another portion may be hosted by or part of application processor 1512, while one or more portions of spill/fill mechanism 1510 may be hosted by or part of operating system 1506 and/or any number and type of devices of computing device 1500. It is contemplated that embodiments are not limited to any particular implementation or hosting of spill/fill mechanism 1510 and that one or more portions or components of spill/fill mechanism 1510 may be employed or implemented as hardware, software, or any combination thereof, such as firmware.

In the illustrated embodiment, graphics processor 1514 is shown as hosting a novel spill/fill hardware unit 1520 and an array of registers 1530 such that hardware unit 1520 works with spill/fill mechanism 1510 to ensure efficient spilling and filling of registers 1530 in communication with memory 1508. This will be further described with reference to FIG. 16.

Computing device 1500 may host network interface(s) to provide access to a network, such as a LAN, a wide area network (WAN), a metropolitan area network (MAN), a personal area network (PAN), Bluetooth, a cloud network, a mobile network (e.g., 3^(rd) Generation (3G), 4^(th) Generation (4G), etc.), an intranet, the Internet, etc. Network interface(s) may include, for example, a wireless network interface having antenna, which may represent one or more antenna(e). Network interface(s) may also include, for example, a wired network interface to communicate with remote devices via network cable, which may be, for example, an Ethernet cable, a coaxial cable, a fiber optic cable, a serial cable, or a parallel cable.

Embodiments may be provided, for example, as a computer program product which may include one or more machine-readable media having stored thereon machine-executable instructions that, when executed by one or more machines such as a computer, network of computers, or other electronic devices, may result in the one or more machines carrying out operations in accordance with embodiments described herein. A machine-readable medium may include, but is not limited to, floppy diskettes, optical disks, CD-ROMs (Compact Disc-Read Only Memories), and magneto-optical disks, ROMs, RAMs, EPROMs (Erasable Programmable Read Only Memories), EEPROMs (Electrically Erasable Programmable Read Only Memories), magnetic or optical cards, flash memory, or other type of media/machine-readable medium suitable for storing machine-executable instructions.

Moreover, embodiments may be downloaded as a computer program product, wherein the program may be transferred from a remote computer (e.g., a server) to a requesting computer (e.g., a client) by way of one or more data signals embodied in and/or modulated by a carrier wave or other propagation medium via a communication link (e.g., a modem and/or network connection).

Throughout the document, term “user” may be interchangeably referred to as “viewer”, “observer”, “person”, “individual”, “end-user”, and/or the like. It is to be noted that throughout this document, terms like “graphics domain” may be referenced interchangeably with “graphics processing unit”, “graphics processor”, or simply “GPU” and similarly, “CPU domain” or “host domain” may be referenced interchangeably with “computer processing unit”, “application processor”, or simply “CPU”.

It is to be noted that terms like “node”, “computing node”, “server”, “server device”, “cloud computer”, “cloud server”, “cloud server computer”, “machine”, “host machine”, “device”, “computing device”, “computer”, “computing system”, and the like, may be used interchangeably throughout this document. It is to be further noted that terms like “application”, “software application”, “program”, “software program”, “package”, “software package”, and the like, may be used interchangeably throughout this document. Also, terms like “job”, “input”, “request”, “message”, and the like, may be used interchangeably throughout this document.

FIG. 16 illustrates smart spill/fill mechanism 1510 of FIG. 15 according to one embodiment. For brevity, many of the details already discussed with reference to FIGS. 1-15 are not repeated or discussed hereafter. In one embodiment, spill/fill mechanism 1510 may include any number and type of components, such as (without limitations): detection/observation logic 1601; prediction/division logic 1603; computation/compilation logic 1605; communication/compatibility logic 1607; and processing/transferring logic 1609.

As previously described, execution of graphics kernel programs on a hardware architecture may be faster and more energy efficient, if executed in a higher SIMD mode (e.g., SIMD16 mode as opposed to SIMD8 mode). However, compiling a kernel in a higher SIMD mode necessitates more general-purpose registers to be available per thread (such as approximately doubled for a higher SIMD mode). It is contemplated that spilling occurs when the kernel needs more registers than there are available for a single thread. This spilling of registers refers to moving the contents of the registers to a higher capacity component, such as memory 1508 (e.g., RAM), which is an order of magnitude slower memory. Thus, spilling of general-purpose registers to memory 1508 typically reduces the potential performance gain of compiling kernels for a higher SIMD mode.

It is contemplated that a “kernel” may refer to a core component associated with an operation system, such as operating system 1506 of FIG. 15, component serving as an intermediary or a bridge between one or more software levels (e.g., software applications, drivers, such as driver 1506, etc.) and one or more hardware levels (e.g., application processor 1512, graphics processor 1514, memory 1508, other devices, such as I/O source(s) 1504, etc.) of computing device 1500. For example, a kernel may be regarded as a low-level interface or abstraction layer between software and hardware levels. A kernel may be a computer program having a great deal of control and influence over any number and type of software and/or hardware components within the computing system 1500.

For example, a kernel may be responsible for any number and type of tasks, such as memory allocation and management, task management, application execution, disk/device management through drivers, system calls control and management, input/output requests management, instructions translation tasks, management of I/O source(s)/device(s) 1504, such as keyboards, speakers, display devices, etc. There may be any number and type of kernels, such as (without limitation) monolithic kernels, microkernels, exo kernels, nano kernels, and hybrid kernels.

Conventional techniques avoid, when acceptable by application programming interface (API), higher SIMD kernels if they incur spilling into memory and consequently, potentially losing out of some gains of higher SIMD execution. Another conventional or classical approach involves spilling registers “point-wise”.

To reclaim typical drop in performance due to spill code, embodiments provide for a novel technique based on a hardware/software solution for execution kernels in higher SIMD modes even if the maximum register requirement exceeds the number of available registers per thread. Further, as facilitated by spill/fill mechanism 1510, this novel technique is based on dividing the kernel to be executed into regions or chunks of low and high register pressure and execution of bulk data transfers between general purpose registers and backing (high-latency) memory.

For example, a number of top shaders (e.g., longest time execution kernels) in top games available today are limited to being compiled in lower SIMD8 mode. Today's GPUs can support multiple SIMD modes of program kernel compilation, such as SIMD8, SIMD16, and SIMD 32. Compiling a kernel for a higher SIMD may necessitate higher number of available hardware registers (e.g., a single vector register for SIMD16 can occupy twice as much space as that for SIMD8).

For example, if a kernel compiled for a given SIMD mode needs more registers than the available registers, then spill-fill code may be inserted to move data into/from spill memory (e.g., scratch memory). A conventional approach for inserting spill-fill code deals with inserting piecewise write/read operations directly into the kernel code, where instructions are inserted at points determined by a register allocator cost-model (usually, variables are evicted that release the longest possible live-range).

Conventional solutions for compiling kernels in high SIMD modes including inserting the piecewise spill/fill code in the kernel, where classical register allocation algorithm places piecewise (single-data item) transfers of registers into scratch memory and back. Such techniques cause a lot of single-date memory read and write operations affecting performance of kernel execution. Another conventional solution is to compile a kernel in a lower SIMD mode, reducing the potential of performance gains of higher SIMD mode execution.

To enable compilation in higher SIMD modes, while avoiding performance degradation as experienced with conventional spill/fill code, one embodiment provides for an improved and efficient approach that uses block transfers by dedicated hardware unit 1520. For example, in one embodiment, a better performance of spill/fill data transfers is achieved by having hardware unit 1520 take advantage of parallel and aligned transfers where cache memory may be used more efficiently.

In contrast, embodiments provide for a novel technique for handling spill/fill using a bulk approach, such as a block of hardware registers 1530 is transferred into/from backing (e.g., scratch) memory 1508 by a dedicated hardware unit, such as hardware unit 1520. For example, when a transfer is requested, a hardware thread is preempted and relinquishes control until the transfer is finished such that any of the other threads may continue to perform their tasks.

Embodiments provide for a novel technique using certain cooperating parts as supported and facilitated by spill/fill mechanism 1510, where the cooperating parts include (without limitations): 1) compiler code generation algorithm that inserts appropriate register blocks from registers 1530 to memory 1508 transfers and vice versa as facilitated by processing/transferring logic 1609; and 2) special hardware support, as offered by hardware unit 1520, for register block transfer into backing memory instructions (e.g., spill) and the corresponding memory block transfer into register block transfer instructions (e.g., fill).

With regard to compiler code generation algorithm, in one embodiment, a compiler, as facilitated by prediction/division logic 1603, may be used to divide the control flow graph of a kernel into regions of high and low register pressures, where the register pressure of an entire region may be defined as maximum pressure. In one embodiment, this division may be based on a predetermined threshold, such as the number of hardware registers 1530, where an effective threshold may be defined as: Effective_Thold=MIN(Thold, NumHwRegisters).

For example, for each region of high register pressure, a set of live-through variables is computed, where the register allocation scheme is modified in such a way that live-through variables for a region are allocated in a contiguous block of hardware registers 1530. Further, as facilitated by processing/transferring logic 1609, the compiler inserts a register block transfer from registers 1530 to memory 1508 before each region of high register pressure from a set of live-through variables, where a memory area in the backing memory is allocated by a compiler for a given transfer.

A block transfer from backing memory of memory 1508 to a block of hardware registers of registers 1530 is inserted by the compiler, as facilitated by processing/transferring logic 1609, after a region of high register pressure. Such processes are applied iteratively until all regions of high register pressure are processed.

With regard to block transfer instructions, registers 1530 to memory 1520 block transfer (“R2MBT”) instruction initiate a transfer of a block of N consecutive registers from registers 1530 into a given offset in backing (scratch) memory of memory 1508 as facilitated by processing/transferring logic 1609. After the transfer is initiated, dedicated hardware unit 1520 is initiated by processing/transferring logic 1609 to perform the data transfer, while the main executed thread is preempted and relinquishes the control such that a different hardware thread may continue to perform its operations or tasks if not in a wait state.

Similarly, memory 1520 to registers 1530 block transfer (“M2RBT”) instruction initiates a transfer of a block of N consecutive memory locations into a given block of consecutive registers (addressable by a starting register number) of registers 1530 as facilitated by processing/transferring logic 1609. After the transfer is initiated, dedicated hardware unit 1520 is initiated to perform the data transfer, while the main execution thread is preempted and relinquishes the control such that a different hardware thread may continue its operations or tasks if not in a wait state.

For both types of transfers, such as R2MBT and M2RBT, after dedicated hardware unit 1520 finishes the requested operation, the initiating executing thread is marked as available for execution and continues its execution of instructions in the following region as soon as possible.

Embodiments provide for a novel technique where detection/observation logic 1601 may be used to perform detection or observation of the register capacity of graphics processor 1514 along with detecting the type of software application (e.g., three-dimensional (3D) application, such as a game, etc.) that may be running or expected to run on computing device 1500 to be processed and executed by graphics processor 1514. Once the initial detection and observation of various components and players is performed, prediction/division logic 1603 may be triggered to evaluate the information available or received from detection/observation logic 1601 to then determine or predict the form or sequence in which the software application may run, such as when the use of registers 1530 by the application may be high or low.

Stated differently, in one embodiment, prediction/division logic 1603 predicts the performance highs and lows of the software application and then, in turn, predicts the corresponding the highs and lows of the use of registers 1530 by the software application. This prediction of the use allows for prediction/division logic 1603 to divide the kernels into regions and work with hardware unit 1520 at graphics processor 1514 to ensure timely spilling and filling of registers 1530, resulting in an efficient transfer of data.

For example, as facilitated by prediction/division logic 1603, a compiler may generate a kernel code to initiate transfers at designated or necessary points, where the compiler is further facilitated by prediction/division logic 1603 to divide the kernel code into regions or chunks of low and/or high register pressure. The bulk transfer may be initiated in-between regions, such as between the low-pressure and high-pressure regions such that a transfer from a hardware block of registers 1530 into the scratch memory at memory 1508 is initiated (to release the necessary number of registers for the high-pressure region, which may be regarded as the counterpart to the classical spill code). Similarly, between high-pression and low-pression regions, a transfer is initiated to move back the data from scratch memory at memory 1508 into registers 1530 (which may be regarded as the counterpart to the fill code).

For example, as shown in the graph with respect to FIG. 17A, prediction of how a software application may perform overtime in terms of its need for the use for registers 1530 (such as lower demand in the beginning when the software application first starts and then much higher demand later when the software application is performing at its peak) may allow for advanced planning of spilling and filling of registers 1530 based on the highs and lows of the demand. This novel technique allows for a better distribution of the use of the limited number of registers 1530 without having to require more registers, additional hardware, slowing down of the software application, or bottlenecking of system resources.

For example, in one embodiment, computation/compilation logic 1605 may be used to perform compilation and computation tasks, such as insertion of register block transfers from registers to memory 1508 before each region of high register pressure for a set of live-through variables, such as a memory area in backing memory, such as memory 1508, may be allocated by a compiler, as facilitated by computation/compilation logic 1605, for the given transfer. Similarly, a block transfer from a backing memory to a block of hardware register 1630 may be inserted after a region of high register pressure. This may continue until all regions of high register pressure are processed. This transferring between registers 1530 and memory 1508 and vice versa may be performed facilitated by processing/transferring logic 1609.

Computing device 1500 is further shown to be in communication with one or more repositories, datasets, and/or databases, such as database(s) 1630 (e.g., cloud storage, non-cloud storage, etc.), where database(s) 1630 may reside at a local storage or a remote storage over communication medium(s) 1625, such as one or more networks (e.g., cloud network, proximity network, mobile network, intranet, Internet, etc.).

It is contemplated that a software application running at computing device 1500 may be responsible for performing or facilitating performance of any number and type of tasks using one or more components (e.g., GPU 1514, graphics driver 1516, CPU 1512, etc.) of computing device 1500. When performing such tasks, as defined by the software application, one or more components, such as GPU 1514, graphics driver 1516, CPU 1512, etc., may communicate with each other to ensure accurate and timely processing and completion of those tasks.

Communication/compatibility logic 1607 may be used to facilitate the needed communication and compatibility between any number of devices of computing device 1500 and various components of spill/fill mechanism 1510.

Communication/compatibility logic 1607 may be used to facilitate dynamic communication and compatibility between computing device 1500 and any number and type of other computing devices (such as mobile computing device, desktop computer, server computing device, etc.); processing devices or components (such as CPUs, GPUs, etc.); capturing/sensing/detecting devices (such as capturing/sensing components including cameras, depth sensing cameras, camera sensors, red green blue (RGB) sensors, microphones, etc.); display devices (such as output components including display screens, display areas, display projectors, etc.); user/context-awareness components and/or identification/verification sensors/devices (such as biometric sensors/detectors, scanners, etc.); database(s) 1630, such as memory or storage devices, databases, and/or data sources (such as data storage devices, hard drives, solid-state drives, hard disks, memory cards or devices, memory circuits, etc.); communication medium(s) 1625, such as one or more communication channels or networks (e.g., Cloud network, the Internet, intranet, cellular network, proximity networks, such as Bluetooth, Bluetooth low energy (BLE), Bluetooth Smart, Wi-Fi proximity, Radio Frequency Identification (RFID), Near Field Communication (NFC), Body Area Network (BAN), etc.); wireless or wired communications and relevant protocols (e.g., Wi-Fi®, WiMAX, Ethernet, etc.); connectivity and location management techniques; software applications/websites (e.g., social and/or business networking websites, etc., business applications, games and other entertainment applications, etc.); and programming languages, etc., while ensuring compatibility with changing technologies, parameters, protocols, standards, etc.

Throughout this document, terms like “logic”, “component”, “module”, “framework”, “engine”, “mechanism”, and the like, may be referenced interchangeably and include, by way of example, software, hardware, and/or any combination of software and hardware, such as firmware. In one example, “logic” may refer to or include a software component that is capable of working with one or more of an operating system (e.g., operating system 1506), a graphics driver (e.g., graphics driver 1516), etc., of a computing device, such as computing device 1500. In another example, “logic” may refer to or include a hardware component that is capable of being physically installed along with or as part of one or more system hardware elements, such as an application processor (e.g., CPU 1512), a graphics processor (e.g., GPU 1514), etc., of a computing device, such as computing device 1500. In yet another embodiment, “logic” may refer to or include a firmware component that is capable of being part of system firmware, such as firmware of an application processor (e.g., CPU 1512) or a graphics processor (e.g., GPU 1514), etc., of a computing device, such as computing device 1500.

Further, any use of a particular brand, word, term, phrase, name, and/or acronym, such as “spill/fill”, “spilling registers”, “filling registers”, “memory”, “hardware unit”, “registers”, “transferring from registers to memory”, “transferring from memory to registers”, “dividing kernel into regions or chunks”, “compiler”, “GPU”, “GPU domain”, “GPGPU”, “CPU”, “CPU domain”, “graphics driver”, “workload”, “application”, “graphics pipeline”, “pipeline processes”, “register”, “register file”, “RF”, “extended register file”, “ERF”, “execution unit”, “EU”, “instruction”, “API”, “3D API”, “OpenGL®”, “DirectX®”, “fragment shader”, “YUV texture”, “shader execution”, “existing UAV capabilities”, “existing backend”, “hardware”, “software”, “agent”, “graphics driver”, “kernel mode graphics driver”, “user-mode driver”, “user-mode driver framework”, “buffer”, “graphics buffer”, “task”, “process”, “operation”, “software application”, “game”, etc., should not be read to limit embodiments to software or devices that carry that label in products or in literature external to this document.

It is contemplated that any number and type of components may be added to and/or removed from spill/fill mechanism 1510 to facilitate various embodiments including adding, removing, and/or enhancing certain features. For brevity, clarity, and ease of understanding of spill/fill mechanism 1510, many of the standard and/or known components, such as those of a computing device, are not shown or discussed here. It is contemplated that embodiments, as described herein, are not limited to any particular technology, topology, system, architecture, and/or standard and are dynamic enough to adopt and adapt to any future changes.

FIG. 17A illustrates a graph 1700 of injection points for block write(s) and block read(s) instructions in a kernel. For brevity, many of the details previously discussed with reference to FIGS. 1-16 may not be discussed or repeated hereafter. It is contemplated that embodiments are not limited to this illustration.

As illustrated, graph 1700 shows injection points of a software application or program (e.g., 3D gaming application) running on a computing device. For example, it is contemplated that as the application initiates its run at the computing device, its first kernel instruction 1713 from instructions 1711 is relatively low or virtually zero in terms of register pressure 1703. With the passing of time and instructions 1711, such as at an injection point of block write instruction 1715, the software application begins to do more and/or bigger tasks and accordingly, jumping in its needs for the use of registers, nearly reaching high pressure threshold 1707 as indicating by line 1701.

Similarly, at point in time between block write instruction 1715 and a subsequent injection point of block read instruction 1717, line 1701 representing the software application rises to not only surpass high pressure threshold 1707, but also the total number of hardware registers, as shown by line 1705, that might be available at the graphics processor of the computing device. As the software application nears and reaches last kernel instruction 1719 its need or use for registers and other system resources is drastically lowered as indicated by line 1701 which is now below both lines 1707 and 1705 representing the high pressure threshold and the total number of registers.

FIG. 17B illustrates an architectural placement of components for smart register spill/fill at a computing device 1500 according to one embodiment. For brevity, many of the details previously discussed with reference to FIGS. 1-17A may not be discussed or repeated hereafter. It is contemplated that embodiments are not limited to this illustration.

As illustrated, in one embodiment, computing device 1500 is shown as having graphics driver 1516 hosting spill/fill mechanism 1510 in communication with application processor 1512 and graphics processor 1514. Application processor 1512 is shown as having display driver 1725 in communication with software application 1721 (e.g., 3D application) and compiler 1723 in communication with spill fill mechanism 1510 at graphics driver 1516. Computing device 1500 is further shown as hosting graphics processor 1514 which further includes spill/fill hardware unit 1520 (e.g., block transfer unit), one or more execution units (EUs) 1 1731A, 2 1731B, 3 1731M, m+1 1751A, m+2 1751B, and n 1751N employing and/or corresponding to one or more registers 1741A, 1741B, 1741M, 1761A, 1761B, and 1761N. It is contemplated that registers 1741A-M, 1761A-N are the same as or part of registers 1530 of FIG. 15.

As discussed throughout this document, spill/fill mechanism 1510 works with compiler 1723 and hardware unit 1520 to facilitate any number and type of efficient spill/fill-related operations and tasks, such as communicating graphics program (shader) with high-level instructions with software application 1721, and graphics kernel with hardware (assembler) instructions with hardware unit 1520 at graphics processor 1514. As described with reference to FIG. 16, spilling/filling of registers is performed through inputting/outputting of data (e.g., read input data, write output data) between registers 1741A-M, 1751A-N and memory 1508 (e.g., RAM) via memory I/O with memory cache 1735 at graphics processor 1514. This continues with shader input data (e.g., textures) and shader output results being communicated between memory 1508 and software application 1721.

FIG. 18A illustrates a transaction sequence 1800 for facilitating efficient spilling/filling operations according to one embodiment. For brevity, many of the details previously discussed with reference to FIGS. 1-17B may not be discussed or repeated hereafter. Any processes relating to transaction sequence 1800 may be performed by processing logic that may comprise hardware (e.g., circuitry, dedicated logic, programmable logic, etc.), software (such as instructions run on a processing device), or a combination thereof, as facilitated by spill/fill mechanism 1510 of FIG. 15. The processes associated with transaction sequence 1800 may be illustrated or recited in linear sequences for brevity and clarity in presentation; however, it is contemplated that any number of them can be performed in parallel, asynchronously, or in different orders.

In one embodiment, as illustrated, software program or application 1721 is shown as being running at an application processor executing input shader (kernel) 1803 resulting in output (optimized) assembly code 1807 with R2MBT and M2RBT instructions being inserted as facilitated by compiler through one or more compiler-based processes 1805. Such compiler-based processes may include construction of a control-flow-graph (CFG), dividing of the CFG into regions (looping for each regions), computing pressure for each region, inserting R2MBT instructions at low/high pressure region transitions along with M2RBT instructions at high/low precession regions transitions.

In one embodiment, this output assembly code 1807 is then fed into one or more execution units of a graphics processor, such as EU 1731A of FIG. 17B. In receiving output assembly code 1807 having R2MBT and/or M2RBT instructions, at block 1811, a determination is made as to whether there are any more instructions. If not, the thread ends at block 1813. If yes, the process continues at block 1815 with another determination as to whether any of the instructions are regular. If yes, the process continues at block 1817 with execution of the regular instructions and then proceeds to block 1811 with renewed a determination with respect to any additional instructions. If no regular instructions are detected at block 1815, then at block 1819, another determination is made as to whether there is any R2MBT. If not, at block 1821, a transfer of a block of N consecutive memory locations into a given block of consecutive registers is initiated. If yes, at block 1823, a transfer of a block of N consecutive registers into a given offset in backing (scratch) memory is initiated.

In either case, in one embodiment, at block 1825, a determination is made as to whether the transfer is ready to be performed. If not, the process continues in the look along block 1825 to keep checking on the transfer readiness of the system until the transfer is ready to be performed. If yes, hardware unit 1520, such as a block transfer unit, is triggered to complete the transfer, such as asynchronous transfer at block 1827, and the process may subsequently return to block 1811 with another renewed determination with regard to whether there are any more instructions.

FIG. 18B illustrates a transaction sequence 1850 for facilitating efficient spilling/filling operations according to one embodiment. For brevity, many of the details previously discussed with reference to FIGS. 1-18A may not be discussed or repeated hereafter. Any processes relating to transaction sequence 1850 may be performed by processing logic that may comprise hardware (e.g., circuitry, dedicated logic, programmable logic, etc.), software (such as instructions run on a processing device), or a combination thereof, as facilitated by spill/fill mechanism 1510 of FIG. 15. The processes associated with transaction sequence 1850 may be illustrated or recited in linear sequences for brevity and clarity in presentation; however, it is contemplated that any number of them can be performed in parallel, asynchronously, or in different orders.

As described earlier, a low pressure region, such as R1, may be detected and classified as such at 1851. Similarly, a high pressure region, such as R2, may be detected and classified as such at 1853, while another low pressure region, such as R3, may be detected and classified as such at 1855. In one embodiment, at 1857, one or more compiler-based processes for region may be performed by a compiler as facilitated by spill/fill mechanism 1510 of FIG. 15, where such processes may include computing sets S1 and S2 for region R2, where S1 refers to a set of live-through registers for region R2, and S2 refers to a subset of S1 such that registers in S2 form contiguous numbers such that S2 are chosen for spill (such as transfer to memory).

In one embodiment, at 1859, R2MBT instructions are inserted at low/high pressure region transition at R1, while, at 1861, M2RBT instructions are inserted at high/low pressure region transition at R3.

References to “one embodiment”, “an embodiment”, “example embodiment”, “various embodiments”, etc., indicate that the embodiment(s) so described may include particular features, structures, or characteristics, but not every embodiment necessarily includes the particular features, structures, or characteristics. Further, some embodiments may have some, all, or none of the features described for other embodiments.

In the foregoing specification, embodiments have been described with reference to specific exemplary embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of embodiments as set forth in the appended claims. The Specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

In the following description and claims, the term “coupled” along with its derivatives, may be used. “Coupled” is used to indicate that two or more elements co-operate or interact with each other, but they may or may not have intervening physical or electrical components between them.

As used in the claims, unless otherwise specified the use of the ordinal adjectives “first”, “second”, “third”, etc., to describe a common element, merely indicate that different instances of like elements are being referred to, and are not intended to imply that the elements so described must be in a given sequence, either temporally, spatially, in ranking, or in any other manner.

The following clauses and/or examples pertain to further embodiments or examples. Specifics in the examples may be used anywhere in one or more embodiments. The various features of the different embodiments or examples may be variously combined with some features included and others excluded to suit a variety of different applications. Examples may include subject matter such as a method, means for performing acts of the method, at least one machine-readable medium including instructions that, when performed by a machine cause the machine to perform acts of the method, or of an apparatus or system for facilitating hybrid communication according to embodiments and examples described herein.

Some embodiments pertain to Example 1 that includes an apparatus to facilitate smart spill/fill data transfers in computing environments, the apparatus comprising: prediction/division logic to divide a kernel into regions including low pressure regions and high pressure regions, wherein the low pressure regions are associated with low use of registers hosted by a processor of the apparatus, while the high pressure regions are associated with high use of the registers; and processing/transferring logic to facilitate transfer of data between memory and the registers based on at least one of the low pressure regions and the high pressure regions.

Example 2 includes the subject matter of Example 1, further comprising detection/observation logic to detect processing behavior of one or more components of the apparatus to observe a first demand by a component for the low use corresponding to the low pressure regions, and a second demand by the component for the high use corresponding to the high pressure regions, wherein the one or more components include one or more of software applications and hardware components, wherein the kernel being a component of an operating system is associated with the one or more of the software applications and the hardware components.

Example 3 includes the subject matter of Examples 1-2, wherein the prediction/division logic is further to predict the low and high pressure regions based on the first and second demands, respectively, wherein the prediction/division logic is further to predict whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.

Example 4 includes the subject matter of Examples 1-3, further comprising computation/compilation logic to compute a first set of the data associated with low pressure regions and a second set of the data associated with the high pressure regions, wherein the computation/compilation logic is further to compile a code to predictively schedule a first transfer of the first data from the memory to the registers and a second transfer of the second data set from the registers to the memory, wherein the data includes one or more of write blocks and read blocks.

Example 5 includes the subject matter of Examples 1-4, wherein the processor comprises a spill/fill hardware unit including a data transfer block to transfer the first data set from the memory to the registers representing a fill of the registers, and the second data set from the registers to the memory representing a spill of the registers.

Example 6 includes the subject matter of Examples 1-5, wherein the registers comprise hardware registers such that a block of the hardware registers is transferred into or from a scratch memory by the hardware unit, while a hardware thread associated with the block is preempted and facilitated to relinquish control until a transfer is completed, wherein one or more other hardware threads continue to perform one or more tasks.

Example 7 includes the subject matter of Examples 1-6, wherein the processor comprises a graphics processor co-located with an application processor on a common semiconductor package.

Some embodiments pertain to Example 8 that includes a method for facilitating smart spill/fill data transfer in computing environments, the method comprising: dividing a kernel into regions including low pressure regions and high pressure regions, wherein the low pressure regions are associated with low use of registers hosted by a processor of a computing device, while the high pressure regions are associated with high use of the registers; and transferring of data between memory and the registers based on at least one of the low pressure regions and the high pressure regions.

Example 9 includes the subject matter of Example 8, further comprising detecting processing behavior of one or more components of the computing device, wherein detecting includes observing a first demand by a component for the low use corresponding to the low pressure regions, and a second demand by the component for the high use corresponding to the high pressure regions, wherein the one or more components include one or more of software applications and hardware components, wherein the kernel being a component of an operating system is associated with the one or more of the software applications and the hardware components.

Example 10 includes the subject matter of Examples 8-9, further comprising: predicting the low and high pressure regions based on the first and second demands, respectively; and predicting whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.

Example 11 includes the subject matter of Examples 8-10, further comprising: computing a first set of the data associated with low pressure regions and a second set of the data associated with the high pressure regions; and compiling a code to predictively schedule a first transfer of the first data from the memory to the registers and a second transfer of the second data set from the registers to the memory, wherein the data includes one or more of write blocks and read blocks.

Example 12 includes the subject matter of Examples 8-11, further comprising transferring, by a spill/fill hardware unit including a data transfer block, the first data set from the memory to the registers representing a fill of the registers, and the second data set from the registers to the memory representing a spill of the registers.

Example 13 includes the subject matter of Examples 8-12, wherein the registers comprise hardware registers such that a block of the hardware registers is transferred into or from a scratch memory by the hardware unit, while a hardware thread associated with the block is preempted and facilitated to relinquish control until a transfer is completed, wherein one or more other hardware threads continue to perform one or more tasks.

Example 14 includes the subject matter of Examples 8-13, wherein the processor comprises a graphics processor co-located with an application processor on a common semiconductor package.

Some embodiments pertain to Example 15 includes a data processing system comprising a computing device including a storage device having instructions, and a processor to execute the instructions, wherein the processor to: divide a kernel into regions including low pressure regions and high pressure regions, wherein the low pressure regions are associated with low use of registers hosted by a processor of the computing device, while the high pressure regions are associated with high use of the registers; and transfer of data between memory and the registers based on at least one of the low pressure regions and the high pressure regions.

Example 16 includes the subject matter of Example 15, wherein the processor is further to detect processing behavior of one or more components of the computing device, wherein detecting includes observing a first demand by a component for the low use corresponding to the low pressure regions, and a second demand by the component for the high use corresponding to the high pressure regions, wherein the one or more components include one or more of software applications and hardware components, wherein the kernel being a component of an operating system is associated with the one or more of the software applications and the hardware components.

Example 17 includes the subject matter of Examples 15-16, wherein the processor is further to: predict the low and high pressure regions based on the first and second demands, respectively; and predict whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.

Example 18 includes the subject matter of Examples 15-17, wherein the processor is further to: compute a first set of the data associated with low pressure regions and a second set of the data associated with the high pressure regions; and compile a code to predictively schedule a first transfer of the first data from the memory to the registers and a second transfer of the second data set from the registers to the memory, wherein the data includes one or more of write blocks and read blocks.

Example 19 includes the subject matter of Examples 15-18, wherein the processor comprises a spill/fill hardware unit including a data transfer block to transfer the first data set from the memory to the registers representing a fill of the registers, and the second data set from the registers to the memory representing a spill of the registers.

Example 20 includes the subject matter of Examples 15-19, wherein the registers comprise hardware registers such that a block of the hardware registers is transferred into or from a scratch memory by the hardware unit, while a hardware thread associated with the block is preempted and facilitated to relinquish control until a transfer is completed, wherein one or more other hardware threads continue to perform one or more tasks.

Example 21 includes the subject matter of Examples 15-20, wherein the processor comprises a graphics processor co-located with an application processor on a common semiconductor package.

Some embodiments pertain to Example 22 includes an apparatus comprising: means for dividing a kernel into regions including low pressure regions and high pressure regions, wherein the low pressure regions are associated with low use of registers hosted by a processor of a computing device, while the high pressure regions are associated with high use of the registers; and means for transferring of data between memory and the registers based on at least one of the low pressure regions and the high pressure regions.

Example 23 includes the subject matter of Example 22, further comprising means for detecting processing behavior of one or more components of the computing device, wherein the means for detecting includes means for observing a first demand by a component for the low use corresponding to the low pressure regions, and a second demand by the component for the high use corresponding to the high pressure regions, wherein the one or more components include one or more of software applications and hardware components, wherein the kernel being a component of an operating system is associated with the one or more of the software applications and the hardware components.

Example 24 includes the subject matter of Examples 22-23, further comprising: means for predicting the low and high pressure regions based on the first and second demands, respectively; and means for predicting whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.

Example 25 includes the subject matter of Examples 22-24, further comprising: means for computing a first set of the data associated with low pressure regions and a second set of the data associated with the high pressure regions; and means for compiling a code to predictively schedule a first transfer of the first data from the memory to the registers and a second transfer of the second data set from the registers to the memory, wherein the data includes one or more of write blocks and read blocks.

Example 26 includes the subject matter of Examples 22-25, further comprising means for transferring, by a spill/fill hardware unit including a data transfer block, the first data set from the memory to the registers representing a fill of the registers, and the second data set from the registers to the memory representing a spill of the registers.

Example 27 includes the subject matter of Examples 22-26, wherein the registers comprise hardware registers such that a block of the hardware registers is transferred into or from a scratch memory by the hardware unit, while a hardware thread associated with the block is preempted and facilitated to relinquish control until a transfer is completed, wherein one or more other hardware threads continue to perform one or more tasks.

Example 28 includes the subject matter of Examples 22-27, wherein the processor comprises a graphics processor co-located with an application processor on a common semiconductor package

Example 29 includes at least one non-transitory or tangible machine-readable medium comprising a plurality of instructions, when executed on a computing device, to implement or perform a method as claimed in any of claims or examples 8-14.

Example 30 includes at least one machine-readable medium comprising a plurality of instructions, when executed on a computing device, to implement or perform a method as claimed in any of claims or examples 8-14.

Example 31 includes a system comprising a mechanism to implement or perform a method as claimed in any of claims or examples 8-14.

Example 32 includes an apparatus comprising means for performing a method as claimed in any of claims or examples 8-14.

Example 33 includes a computing device arranged to implement or perform a method as claimed in any of claims or examples 8-14.

Example 34 includes a communications device arranged to implement or perform a method as claimed in any of claims or examples 8-14.

Example 35 includes at least one machine-readable medium comprising a plurality of instructions, when executed on a computing device, to implement or perform a method or realize an apparatus as claimed in any preceding claims.

Example 36 includes at least one non-transitory or tangible machine-readable medium comprising a plurality of instructions, when executed on a computing device, to implement or perform a method or realize an apparatus as claimed in any preceding claims.

Example 37 includes a system comprising a mechanism to implement or perform a method or realize an apparatus as claimed in any preceding claims.

Example 38 includes an apparatus comprising means to perform a method as claimed in any preceding claims.

Example 39 includes a computing device arranged to implement or perform a method or realize an apparatus as claimed in any preceding claims.

Example 40 includes a communications device arranged to implement or perform a method or realize an apparatus as claimed in any preceding claims.

The drawings and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims. 

What is claimed is:
 1. An apparatus comprising: one or more processors to: divide a kernel into regions including low pressure regions and high pressure regions, wherein the low pressure regions are associated with low use of registers hosted by the one or more processors, while the high pressure regions are associated with high use of the registers; facilitate transfer of data between memory and the registers based on at least one of the low pressure regions and the high pressure regions, wherein the registers comprise a block of hardware registers, and wherein, upon receiving a request for the transfer, one or more hardware threads associated with the block of hardware registers is preempted and facilitated to relinquish control until the transfer is completed, while the one or more hardware threads continue to perform one or more tasks; and predict the low and high pressure regions based on a first demand and a second demand, respectively, and whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.
 2. The apparatus of claim 1, wherein the one or more processors are further to detect processing behavior of one or more components of the apparatus to observe the first demand by a component for the low use corresponding to the low pressure regions, and the second demand by the component for the high use corresponding to the high pressure regions, wherein the one or more components include one or more of software applications and hardware components, wherein the kernel being a component of an operating system is associated with the one or more of the software applications and the hardware components.
 3. The apparatus of claim 2, wherein the one or more processors are further to predict the low and high pressure regions based on the first and second demands, respectively, wherein the one or more processors are further to predict whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.
 4. The apparatus of claim 1, wherein the one or more processors are further to compute a first set of the data associated with low pressure regions and a second set of the data associated with the high pressure regions, wherein the one or more processors are further to compile a code to predictively schedule a first transfer of the first data from the memory to the registers and a second transfer of the second data set from the registers to the memory, wherein the data includes one or more of write blocks and read blocks.
 5. The apparatus of claim 4, wherein a processor of the one or more processors comprises a spill/fill hardware unit including a data transfer block to transfer the first data set from the memory to the registers representing a fill of the registers, and the second data set from the registers to the memory representing a spill of the registers.
 6. The apparatus of claim 5, wherein the processor comprises a graphics processor co-located with an application processor on a common semiconductor package.
 7. A method comprising: dividing a kernel into regions including low pressure regions and high pressure regions, wherein the low pressure regions are associated with low use of registers hosted by one or more processors of a computing device, while the high pressure regions are associated with high use of the registers; transferring of data between memory and the registers based on at least one of the low pressure regions and the high pressure regions, wherein the registers comprise a block of hardware registers, and wherein, upon receiving a request for the transfer, one or more hardware threads associated with the block of hardware registers is preempted and facilitated to relinquish control until the transfer is completed, while the one or more hardware threads continue to perform one or more tasks; and predicting the low and high pressure regions based on a first demand and a second demand, respectively, and whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.
 8. The method of claim 7, further comprising detecting processing behavior of one or more components of the computing device, wherein detecting includes observing the first demand by a component for the low use corresponding to the low pressure regions, and the second demand by the component for the high use corresponding to the high pressure regions, wherein the one or more components include one or more of software applications and hardware components, wherein the kernel being a component of an operating system is associated with the one or more of the software applications and the hardware components.
 9. The method of claim 8, further comprising: predicting the low and high pressure regions based on the first and second demands, respectively; and predicting whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.
 10. The method of claim 7, further comprising: computing a first set of the data associated with low pressure regions and a second set of the data associated with the high pressure regions; and compiling a code to predictively schedule a first transfer of the first data from the memory to the registers and a second transfer of the second data set from the registers to the memory, wherein the data includes one or more of write blocks and read blocks.
 11. The method of claim 10, further comprising transferring, by a spill/fill hardware unit including a data transfer block, the first data set from the memory to the registers representing a fill of the registers, and the second data set from the registers to the memory representing a spill of the registers.
 12. The method of claim 7, wherein a processor of the one or more processors comprises a graphics processor co-located with an application processor on a common semiconductor package.
 13. At least one non-transitory machine-readable storage medium comprising a plurality of instructions, executed on a computing device, to facilitate the computing device to perform operations comprising: dividing a kernel into regions including low pressure regions and high pressure regions, wherein the low pressure regions are associated with low use of registers hosted by one or more processors of the computing device, while the high pressure regions are associated with high use of the registers; transferring of data between memory and the registers based on at least one of the low pressure regions and the high pressure regions, wherein the registers comprise a block of hardware registers, and wherein, upon receiving a request for the transfer, one or more hardware threads associated with the block of hardware registers is preempted and facilitated to relinquish control until the transfer is completed, while the one or more hardware threads continue to perform one or more tasks; and predicting the low and high pressure regions based on a first demand and a second demand, respectively, and whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.
 14. The non-transitory machine-readable storage medium of claim 13, wherein the operations further comprise detecting processing behavior of one or more components of the computing device, wherein detecting includes observing the first demand by a component for the low use corresponding to the low pressure regions, and the second demand by the component for the high use corresponding to the high pressure regions, wherein the one or more components include one or more of software applications and hardware components, wherein the kernel being a component of an operating system is associated with the one or more of the software applications and the hardware components.
 15. The non-transitory machine-readable storage medium of claim 14, wherein the operations further comprise: predicting the low and high pressure regions based on the first and second demands, respectively; and predicting whether the second demand for the high use of the registers is expected to exceed a number of the registers available at the processor.
 16. The non-transitory machine-readable storage medium of claim 13, wherein the operations further comprise: computing a first set of the data associated with low pressure regions and a second set of the data associated with the high pressure regions; and compiling a code to predictively schedule a first transfer of the first data from the memory to the registers and a second transfer of the second data set from the registers to the memory, wherein the data includes one or more of write blocks and read blocks.
 17. The non-transitory machine-readable storage medium of claim 16, wherein the processor comprises a spill/fill hardware unit including a data transfer block to transfer the first data set from the memory to the registers representing a fill of the registers, and the second data set from the registers to the memory representing a spill of the registers. 